The "Charmed" alum broke the news on her blog on Wednesday, explaining why she won't be returning for the ABC drama's third season.
The actress welcomed her second child, daughter Elizabella Dylan, with husband David Bugliari last month. Now that she has a family of four -- she's also mom to son Milo, 3 -- she decided it was in their best interest to stay in the City of Angels so that her family could remain together.
"I have two babies under 4. Being a mother and wife comes first and I just can not uproot my children and separate the family by moving away. I will miss this job desperately and wish everyone the absolute best," the actress concluded.
No word yet on how the show will deal with her exit.