u/BigGreenWEENIE_

Hey im not sure how to say this but im trying to get help on how to find my older brother and sister. I grew up as a single child (30 now) and my mom passed away when I was 10. Recently I was talking to my dad and he told me the truth that my mom had a boy and girl from a previous relationship before I was born. Growing up as a single child I never knew the feeling to have siblings but knowing there's someone out idk I just want to atleast let them know I exist and tell them what happened to mom. My dad wasnt able to tell me anything else about them. He doesnt know their names, birthday or social he just knows they were taken into child protective services. With nothing to go on I have no idea how to even start looking. Any advice?