Not much is known about her life. A few years prior to the first film, she had a daughter with an unknown man.
Alvin and the Chipmunks
She was shopping with her daughter in her cart when her daughter started throwing the boxes at a nearby man. She quickly apologized to Dave Seville, which he understood, saying "Kids, huh?" She asked if he had any, to which he said "Three boys". She told him some days are better than others, to which he then said "And some days you wanna put them in a box, leave the box in the park, and run away". Weirded out, she hurried away.