Duff thinks about the fact that her children have the benefit of growing up alongside the kids of Trainor, Moore, Tisdale and the other moms in their group — many of whom have a lot in common.

Duff opens up to PEOPLE about her celeb-filled friend group of moms — which includes Meghan Trainor, Ashley Tisdale and Mandy Moore Jack Irvin has over five years of experience working in ...