His mum Afeni married lumumba shakur and took his surname, both got locked up but she later got bail and went out, then had a brief relationship with billy garland while she was married to lumumba got pregnant and the bail was revoked and she went back to jail, got acquitted and gave birth to 2pac, she gave him the shakur surname from lumumba who she was still legally married to. lumumba found out the kid wasn't his and they got divorced. Afeni then got into a relationship with lumumba's step brother Mutulu who already had 4 other kids one of these kids was mopreme. They got married and had a daughter Set.
Eventually Afeni got separated and divorced from mutulu and remarried Gus davis but later separated and divorced shortly before passing on.
2pac has 5 half siblings from billy and 6 half siblings including set from mutulu.