In September 2013, Lindsay Chapman-Caroll's six-month-old baby, Leah, was diagnosed with a rare blood disease called severe congenital neutropenia.
The condition makes people very vulnerable to recurring infections, as they don't have enough neutrophils (a type of white blood cell) to fight off infection or reduce inflammation. Ever since then, the Tracy, California, resident has had many hospital visits and survived multiple infections. But despite everything she's dealt with, her amazing spirit still shines through -- especially when she sings along with one of her favorite songs.
In addition to surviving septic shock as an infant, she also overcame E. coli and C. difficile infections.
When she was just over a year old, she received a bone marrow transplant. Two years later, she got a second one and developed Graft versus Host Disease, when donor bone marrow or stem cells attack the recipient.
The now four-year-old has spent nearly all of the last year in hospitals and has had a hard time recovering, but it's pretty clear that she still feels positive and happy when she sings about overcoming her difficulties.