Maher was born on January 10, 2004, to Reuben Edward Maher and Alison Victoria Maher (née Ramlall). She has a younger brother, Ethan Joshua Maher (b. December 18, 2007). When she was eighteen months old, Maher's parents were worried because she was not getting enough sleep. She never stopped singing. Her parents took her to the pediatrician. They found out that she just loved to sing.

In 2008, at the age of 4, she appeared on the third season of America's Got Talent and for her audition sang "Somewhere Out There". She advanced through four rounds of competition and one was of the final ten contestants, the youngest person to ever reach that level.

Semi-final in Amreca's got Talent

"what a wonderful world" -- Louis Armstrong

Ave Maria --- 5 years old

Kaitlyn Maher - 10yo - "Let it Go" (Frozen) - March 9, 2014

In 2013, Maher joined the cast of Fox's new comedy series, The Goodwin Games starring as Piper Goodwin, the daughter of Jimmy Goodwin played by T.J. Miller