Drew Barrymore wanted to create a "real stable home" for her children.
The 39-year-old actress - who didn't see much of her father John when she was growing up as he split from her mother Jaid before she was born - says the most important thing to her is for her daughters Olive, 20 months, and Frankie, two months, to feel "safe" with her and their dad Will Kopelman.
She said: "[I want to create] a real stable home. "I know when my daughter wants to swing higher and jump into the pool and all of these things, she feels safe. To make your kids feel safe is everything."
The 'Blended' actress says it was important for her to have a sibling for Olive because she would have "really liked" to have a brother or sister herself.
And Drew is delighted with how well her eldest child has adjusted to the new arrival.
Showing off her new baby in People magazine for the first time, she said: "Olive loves Frankie and just wants to hang out with her all the time.
"She wants to feed her. She's super into it. That's now. I'm sure things will ebb and flow."
The 'Whip It!' star admits it can be tricky to tend to both her daughters' needs as their schedules are so different.
Asked the biggest challenge of having two kids, she said: "Just being split. They're awake and asleep at different times, or awake at the same time, and it's a juggling act a little bit."
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