Nicole Richie says motherhood is "like nothing I could have imagined"

Nicole Richie is loving motherhood.

"It's definitely like nothing I could have imagined," the socialite, 26, said at the the 25th Annual ASCAP Pop Music Awards in Los Angeles, where she appeared with father Lionel Richie.

Nicole goes on to say that life with daughter Harlow, who was born in January, is "beyond amazing, and my family has been supportive. And I go to my dad's house all the time."

The former 'Simple Life' star says Lionel, 58, is also meeting his grandfatherly obligations as well. "He actually babysat the other day – him and Joel [Madden, Nicole's finacé] – and they were amazing. I mean, she slept the whole time."

Added Lionel: "It's when the baby wakes up that I freak out!"

Lionel, who was honored with an ASCAP Lifetime Achievement Award, also said of his daughter: "She went from, 'Dad, I don't care. Whatever you say.' To 'Wash your hands, Dad' and 'Be quiet Dad.' It's a whole new sound of the house."

And one obstacle that had to be overcome was how Lionel was to be addressed now that his child has had one of her own.

"I went to Nicole and said, 'Grandpa,' how does that sound? Does that fit me?' She said, 'Dad, that sounds old.' So I kind of searched out ... G-Pa sounds a lot better."