My mom have o blood type while my dad got a B blood type how come that both me and my brother have AB blood?

please give an explanation i was really wondering why.. ✅ Answers ? Best Answer Shame and scandal in de family. If you are right, that cannot be your mother. Maybe want to ask if you two were adopted. Source(s): http://askville.amazon.com/child-mother’… Your sure? That cannot possibly be your biological mother. mis print?