The 35-year-old actress wants to have the relationship with her daughter's children that she shared with her own grandmother, reported Contactmusic.
"The Holmes family is enormous. Because my dad was the youngest of five, and I'm the youngest of five, I was the youngest of all the grandchildren.
"(My grandma) used to give me her clip-on earrings, and I thought she was so glamorous. And she used to say to me, 'Katie, you have such pretty eyes... They're just like mine'. I'm going to say that to my many grandkids someday and I can't wait," she said.
"You do the best you can. Some days you feel really good about yourself and some days you don't. You really need to support each other, help people through whatever it is they're going through - whether it's: 'My kid just threw a tantrum' or 'I was late for graduation' or whatever it is, you know!'," she added.