Stepmom and new Mom

Jesse

My husbands ex, the mother of his 2 children, is still in love with him and she has both kids and he sees them on weekends. The kids are 2 and 3. I love both of them and we get along great. Her and I also get along but are by no means besties. just found out I am 6 weeks pregnant. I know this is not going to be happy news for her. I am not sure when or how to tell her. Anyone have any advice?