She moved to Delaware County with her mother and siblings after her father, a Philadelphia firefighter, died by gun suicide.

O'Mara cites the importance of her father's pension and public program such as CHIP in supporting her family while she was a teenager.

[2] She earned a Bachelor of Arts degree in history and a certificate in Secondary Education from West Chester University in 2011.

[8] She was unopposed in the Democratic primary and faced Republican Robert Smythe Jr. in the general election.

[9] O'Mara was sworn in on January 1, 2019, and was elected first vice-chair for the Democratic Caucus's Southeast delegation.