Witherspoon has Ava, 16 and 11-year-old Deacon with ex-husband Ryan Phillippe and Tennessee, two, with current spouse Jim Toth.
The 39-year-old Oscar-winner, whose last film "Hot Pursuit" with Sofia Vergara released this May, said her family comes first, reported Female First.
"My family comes first. I haven't made a movie probably in a year and a half. I'm focused on my business, but also I want to spend time with my teenage daughter. It's terrifying that my oldest child is about to leave (home to go to university). I can't imagine not sitting at the foot of her bed, saying, 'So what happened at school today?'" she said.