For the women out there: When did you decide or feel the urge to have children?

I am in my mid twenties. I am in no rush to have kids, get married…etc. But it is a time where nearly everyone around me is either getting married or having children. I look at my friends who have kids, and I wonder if that could be me down the line….and when I will actually want kids haha. I know I want a family someday, so I am just curious if wanting children “kicks in” at some point. For those of you who want/wanted children, when did you know? For those who didn’t, why not? It’s just mere curiosity :)