This op-ed written by Jenni Balck appeared in SELF. Read the full story here.

Brooke was born healthy. She was gaining weight, being a normal, happy baby. Then all of a sudden she was getting kind of sick and throwing up. Because Brooke was a little sick, at her four-week appointment her pediatrician didn’t give her the second dose of the hepatitis B vaccine she was supposed to get. We just thought maybe it was reflux, that there might be a problem with her food or something. We rescheduled for a week later so Brooke could get the vaccine and have a checkup if she was still sick.

Five days after Brooke’s eight-week appointment her symptoms were getting worse, so I took her back to the doctor. He listened to Brooke’s heart and said, “I feel like I hear something funky with her heart. Let’s send her to a cardiologist to check it out.” I figured that if everything looked good after that, Brooke could continue with her vaccines.

We went to the cardiologist and he did several tests. Eventually he put his head in his hands and said, “If she makes it through the night, she may need a heart transplant.” Brooke was just lying on the bed cooing, and the doctor said, “I don’t even know how she’s cooing. She is very, very sick.” Our whole world turned upside down.

We learned that Brooke had acquired a form of heart disease called dilated cardiomyopathy. They said it was just a random case of bad luck. It was later determined that it was probably caused by a virus. Several of us in our family had been sick—we had colds and sore throats—so whatever virus hit us could have hit her heart. Her heart was enlarged to three times the size it should have been. It was like the size of an adult’s in her little infant body. Over time, it became clear that she needed a transplant, which she ultimately received when she was two.

Between when Brooke was diagnosed and when she got her transplant, she was very sick and weak with heart disease. She was on multiple medications and she was hospitalized several times. She even had to be hospitalized for croup, which doesn’t usually happen. Really any illness could have been detrimental.

Brooke and her brother, Billy, who’s two and a half years older, were really secluded from being with other kids in public places during that time. When Billy was a baby, we did a lot of fun things together—Mommy and Me classes, playgrounds, play areas at the mall, moms’ groups with other babies his age and moms I became friends with. Things like that I wasn’t able to do with Brooke because I couldn’t have her in public areas or anywhere with a bunch of kids who may not have been vaccinated. It was very isolating for me. I had to stop going to the moms’ group with Billy, and I didn’t get to know a lot of moms who had babies Brooke’s age. Billy also wasn’t able to do as much. A lot of his play dates we had to cancel because there were too many germs for him to bring home. We had to get a nanny because we needed somebody to be home all the time. I was working part-time and we had no family in Southern California.

A number of times during those first two years of her life, Brooke would go to the hospital and get an IV of milrinone, a medication that basically gave her heart a break. Hospital staff actually called it a “milrinone tune-up.”

Every time the doctors put Brooke on milrinone, they would wean her off and send her home. But there was always the risk that she would not be able to be weaned off because her heart was too weak to pump without the milrinone, and we’d be stuck in the hospital indefinitely. When she took a serious downward turn at age two she went in for the milrinone again. This time she could not be weaned off. That’s when she was listed for a heart transplant.

Since Brooke’s transplant she has had to take medicine every day to suppress her immune system. Otherwise her body would recognize her heart as a foreign body and attack it. Therefore she also cannot have any live vaccines, like MMR or varicella. In live vaccines they give you a weakened version of the living version of the disease, and your body fights it off and builds up immunity as a result. Because Brooke is immunocompromised her body might not be able to fight it off.

The first year or two after the transplant, Brooke needed to be hospitalized a lot, like at least once a month. She had a lot of skin infections and stomach issues happening—she had MRSA at one point. A lot of that revolved around the types of medications she takes and her weakened immune system.

Before all of this I was absolutely planning on making sure Brooke got all her vaccinations. We fully vaccinated our son, Billy. I did my research beforehand as many parents with time on their hands will do. I’m very big on my sources, maybe more than some because I’m a teacher. I wasn’t going to listen to some celebrity. I looked at the scientific data and made the decision to vaccinate my son per the doctor’s guidelines. I would have done the same for Brooke, but her immune system was too weak for that.

After learning that children can have relatively normal lives after successful heart transplants, we made the decision not to bubble wrap Brooke. I can’t imagine that the family that donated her heart would want her to live that way. I imagine that they did it so she could live the life that their child could not live, so we’ve always made the decision to have Brooke do anything she’s capable of doing. She’s done competitive dance, she’s been on club soccer and snow skiing. But knowing these things are out there, it’s been very scary raising Brooke. I have to be very proactive about protecting her.

When Brooke was very little and took dance classes, I had her take the first class of the day so that I could go in and clean everything before she got there. At that point, she was putting things in her mouth.

When she was in preschool, I would get permission to stand up and talk to the parents at back-to-school night and give a little spiel about how Brooke was vulnerable to getting sick. I would explain how important it is for everyone around her to be vaccinated and for the parents to let me know if their kid was sick.

Luckily right now Brooke goes to the elementary school I teach at, so I feel like I have a lot of control. Everyone knows her and her story. But I do go in and talk to the teachers before school starts. I ask them to let me know if any illnesses are going around the class. That’s partly so I can keep Brooke at home if needed and partly also because the first signs of organ rejection can look like flu symptoms. If she starts throwing up or something, it actually relaxes me to know there’s something going around and half the class is throwing up too. But if she has even a pretty low fever she needs to be hospitalized as a precaution. I need to be aware if there’s a fever going around so that I can plan my schedule around that possibility.

As Brooke develops friendships and wants playdates with kids, I talk to the parents. Before a sleepover or something I make sure I kind of know the family and where they stand on vaccinations. I’ll always start by telling Brooke’s story so they know what she’s been through. And then I’ll end with the fact that she can’t be vaccinated and kind of get their take. I don’t want to come off like that judg-y or paranoid mom, but I do want people to know where I’m coming from. I would hope that if they heard Brooke’s story and everything we’ve been through, they would be respectful of us and her health.

When Brooke is around unvaccinated children, I do talk to the parents and tell them I need to know if their kids have fevers or if they’ve been to certain places. It’s a very awkward conversation. It’s difficult not to have people feel judged. But every parent has to look out for their own kid and I’m doing what I have to do to look out for mine.

I also have to talk to Brooke about it. She has been around kids before who were not vaccinated. I had to talk her through that and explain that for her protection, she wasn’t going to have a sleepover with them or anything. Then there are general precautions we take to not be in tight, crowded areas. We never go to opening night of a movie, for example. We wait until it’s been out a little bit.

I’ve also been very on top of all the coverage of vaccine stories over the past few years. I follow the news quite a bit and keep track of where big outbreaks are and what’s coming around. I ask doctors to let me know when something is happening. It’s always a concern. If there’s measles or whooping cough in the area, then maybe we decline an invitation to a bounce-house party where there are going to be a lot of germs around. That kind of thing has happened a few times since Brooke’s transplant.

When she was in preschool, there was the big measles outbreak in Disneyland. That was pretty scary. It came to our little community and Brooke had to stay home. We had heard that people who had been infected had been in some of the same restaurants we had been to, had been to our doctor’s office. I was very on edge not knowing what it would mean for our family.

Then a few years ago, there was a huge outbreak of the mumps at Ohio State University. I was like, “Shoot, I know she’s not vaccinated against that,” and wondered about whether someone from there would come here.

Just a couple of months ago there were people at schools in our county who had whooping cough. Once that was in our community, I was like, “Oh my gosh, has Brooke already crossed paths with someone who has this?”

In my mind Brooke’s always one illness away from going back into the hospital. We take every possible precaution we can while letting her live her life. But nothing is foolproof. I do all that I can but really it’s out of my control. I absolutely feel helpless sometimes. We can just hope and pray that people make the decision to vaccinate their children because it protects mine, and other kids who can’t get vaccinated like students I’ve had with cancer.

We were very excited when SB-277 went through, which required all kids at school without medical exemptions be vaccinated and got rid of personal choice exemptions. I can feel pretty safe with her at school knowing everyone who can be vaccinated is. But I’ve been very closely following doctors who I believe took it upon themselves to write medical exemptions unnecessarily. I just can’t even fathom that there are doctors who would have such disregard for people who depend on herd immunity. It makes my blood boil. My child and other children truly are in jeopardy here.

Look, I know that every parent is doing the best they can. We’re all winging it. But parents who are deciding not to vaccinate their children could put my child in danger. If they make that choice then I think they need to be homeschooling their kids. I don’t know how to say that nicely. But a school should be a safe place. Parents of children who can’t get vaccinated want to let them out in the world safely. In order for that to happen everyone else who can get vaccinated must.

There is a new law being proposed, SB-276, which says California will keep track of and review the medical exemptions being given. I’m very hopeful that this one goes through because it would mean major protection for my child. That’s why I’ve become so vocal and active in supporting this bill. I testified in a hearing in Sacramento in June. And that’s why Brooke’s pediatrician, Eric Ball, as the president of the American Academy of Pediatrics in Orange County, spoke out about the bill.

Brooke’s been through so much in her short life. She’s had so many surgeries and so many hospital stays. People are generally floored when I mention what she’s been through. She is a super-tough cookie. The problem sometimes lies in how healthy Brooke appears and how much energy she has. Even friends that’ve been in it with us, they sometimes forget that she’s sick. She is just as normal as can be. You can forget she’s delicate.

Next year Brooke will be in middle school, where she’s going to be with all new kids and families that I don’t know. She’s also starting volleyball soon, and there could be unvaccinated kids on her team or the other team. I can’t control who she’s playing against. I don’t know who’s touching the ball. So as she grows, a lot of this is going to be on her. She needs to learn how to share her story, too, and protect herself. I’ve been guiding her through some of that, modeling how to have the conversation with people. Eventually she’ll grow to be an adult and do it all herself.

We have enough anxiety with normal health stuff for Brooke after her heart transplant. I would really have thought that eradicated diseases wouldn’t be at the top of our list of things to worry about. Kids with legitimate health issues and legitimate medical exemptions shouldn’t have to go through that. These kids generally always have a big medical history. They’re endangered and vulnerable and should be able to live the life they’ve struggled to get. They shouldn’t have to deal with this unfair, unnecessary burden. We should do better for them.

Jenni Balck, 47, is an elementary school teacher living in south Orange County, California. Her 10-year-old daughter, Brooke, has been on immunosuppressants ever since she received a heart transplant at age two. Those immune-suppressing medications prevent Brooke’s immune system from attacking her new heart as a foreign body, but they also suppress her immune system to a point that makes her especially vulnerable to infections.

Brooke’s medical history also puts her at serious risk of an adverse reaction to live vaccines—including measles, mumps, and rubella (MMR), polio, and varicella (chicken pox)—because they contain a weakened version of the living pathogen.

In all 50 states and Washington, D.C., it’s mandatory for children to be vaccinated in order to enter day care and private or public school. A small minority of children like Brooke, however, cannot get vaccinated because of a medical condition. These children can qualify for a medical exemption for vaccines, which lasts for as long as the child has a health condition that prevents them from getting live vaccines. This means that Brooke can go to school like other children, but it also means that she’s at a high risk of infection if she’s exposed to something going around—and that includes vaccine-preventable illnesses.