When you first look at precious little Maci’s face, you would probably never guess there was anything different about her. She has adorable chubby cheeks and a sweet smile, just like every other baby.

What you don’t see right away is that Maci is a warrior.

When Maci’s mom, Karissa Whisner, was 20 weeks pregnant, she went in for an ultrasound. As the technician moved the wand over Karissa’s belly, the expectant mom saw something that made her heart drop.

“I knew as a nurse looking at the screen, before they even said anything, that not all of her heart was there,” Karissa recalled.

Maci only had half a heart.

After she was born, doctors found other cardiac defects. Maci was ultimately diagnosed with hypoplastic left heart syndrome (HLHS), double outlet right ventricle (DORV), partial anomalous pulmonary venous return (PAPVR), severe tricuspid regurgitation, multiple ventricular septal defects, a left pulmonary artery sling causing tracheomalacia, pulmonary valve stenosis (PVS), and left pulmonary artery stenosis.

Most babies like Maci don’t survive past a week. Doctors told the family to take Maci home on hospice and make her comfortable for her few days on earth.

But then came a glimmer of hope. Karissa posted about Maci’s condition on Facebook where a local nurse saw it and connected her with Dr. Chris Baird, a pediatrician at Boston Children’s Hospital who is one of the only cardiologists in the world who mends hearts like Maci’s.

“We went from planning her funeral to talking about her future,” Karissa said.

Maci underwent open heart surgery and, after 38 days of recovery, was home and getting stronger.

“She’s a warrior. She’s the strongest little thing I’ve seen in my life,” Maci’s dad, John Whisner, said.

But Karissa knew something still wasn’t right.

“When Maci was born, I immediately felt like she had some kind of genetic syndrome,” she recalled. “I made a list of features that I felt were a bit odd, in hopes that this list would help us find a diagnosis.”

Just a few days after Maci turned one, she was diagnosed with Mowat-Wilson Syndrome. The syndrome is responsible for Maci’s cardiac defects, GI issues, and eye/vision issues, and it also causes moderate to severe intellectual disability.

It’s a diagnosis no parent ever wants to hear, but Karissa and John were determined to give Maci the best life possible.

“Maci is happy and thriving, and she is the light of our lives!” Karissa said. “We wouldn’t change her for the world!”

While Karissa and John were processing everything they had learned about Maci, there was one person Karissa didn’t have the heart to tell about her diagnosis – Maci’s older brother, Jake.

“We haven’t hid it, but we haven’t talked to him about it,” Karissa wrote in a heartrending Facebook post. “I guess because Maci seems fairly ‘typical’ still.”

As Maci gets older, though, her differences and disabilities will become more obvious. Karissa knew she needed to talk to Jake about it, and when he found a magnet that said “Mowat Wilson Syndrome Foundation” and asked her about it, Karissa knew it was time to talk to her son about Maci’s condition.

She didn’t know how he would react to the news, but she definitely wasn’t prepared for what Jake would ask her next.

“He found a magnet from the conference we went to that says ‘Mowat Wilson Syndrome Foundation’ on it,” Karissa wrote. “He asked what it said, so I told him. And then more questions came. ‘What does that mean? Is that why Maci was born with half of a heart?'”

Karissa did her best to answer Jake’s questions truthfully and with grace:

“I explained to him that yes, actually it is why she was born with HLHS, and that it would also make her different in other ways.

“I told him it would make it hard for her to talk, and she may never really talk like us, so that’s why we teach her sign language.

“It might also make it hard for her to walk, so she might walk a little different than us when she’s older or she might need devices to help her walk.

“I explained it might make it harder for her to learn, it might cause her to look a little different, and I went on…’when she is older, she’ll be a little different than us, but..’

As Karissa talked, Jake’s eye grew wide with concern. She was just about to tell him that Maci’s condition would just make her special in her own way, just like everyone is special in their own ways, but then Jake asked her something that blew her out of the water.

“But, will she always want to play with me?! And will she love me?” the sweet boy asked.

“I wanted to cry!” Karissa recalled. “Of course Jake!” she told him. “She will ALWAYS love you and she will always want you to play with her. I think you’ll always be her best friend!'”

With that, Jake ran to Maci and snuggled up right next to her, telling her it was “all okay as long as she would still play with him and love him.”

“What a perfect response,” Karissa wrote. “It showed me the innocence of a child. He couldn’t have cared less if she speaks verbally instead of using signs, or if she has trouble walking, or if she looks different than us.

“He’s my little hero. More than anything, he’s Maci’s hero!”

Despite the struggles they have already been through and those still ahead, Karissa said she wouldn’t change their situation for the world.

“I love this little girl so much,” Karissa wrote in a separate post. “I love her sweet personality. I love her giggles that fill our house every day. I love that she loves her big brother so much. I love that she has a little sense of humor.

“I love that she’s in our lives today. Not a day goes by that I don’t think of how close she came to dying. Every day I hug her extra tight and tell her how much I love her. And then she gives me a big slobbery kiss on the cheek.

“I’d go through hell and back all over again with her to have all that we have now.

“I hope she’s always so happy to be here. I hope we can give her an amazing life while we have her. I hope she always feels loved during her time here on earth.”

Were you touched by Maci’s story and Jake’s sweet heart as much as we were? So share this!