Opinions?

My friend is 17 and she goes out with this boy. The boy has been doing immature SHIT & texting other girls but she still talks to him.he told her him and ex had sex week before my friend birthday but he doesn't count that as cheating because they weren't official yet even though they was talking like they was. But his ex still calling his phone and she told him that she might be pregnant cause she haven't gotten her period in two months. He told her he don't want to be with her and it's not gonna change anything even if he do have a baby.. ( when he found out he was telling her to kill the baby and basically being mean to her ) It's not my business or anything but I really don't feel like my friend should be together. My friend is too young to be experiencing this if his ex girl is pregnant