Nicole Richie's children are having trouble sleeping on tour

She told PEOPLE: "I was very quiet around my kids when they were babies and now they're light sleepers. I wish I had been a little more rough with them."

Nicole also insisted that there is "no one right way" to raise children and she hates when mothers judge each other.

She said: "I had two friends that were moms before me - I had kids very young. It was really so refreshing to see two women that have such different taste and parenting styles maintain a friendship and not judge each other for the way that they bring up their kids."

"That's something that's always stuck with me because there's not one way to raise children. There's no one right way to be a mother. It depends on your house and lifestyle. The biggest lesson I've learned is not to judge!"

Harlow and Sparrow may be young but they already have their own styles, according to Nicole, 34.

She said: "They dress themselves. Sparrow does his own thing. He likes to wear all black like his dad.

"Harlow has her own style. She likes to experiment with different looks. I am totally fine with that. What she looks like is ultimately up to her."