how does that make you feel? >> pissed. >> it's unprecedented for family viewing. ryan seacrest is the producer. >> i hope there is a message of acceptance. and understanding universally we are all kind of the same. >> reporter: ben was 13 years old when carly revealed she was transgendered. how did that hit you? >> like my dad died. seeing my dad as a new stranger i have known. >> reporter: as they transition together viewers see a family bond that seems ultimately unbreakable. >> i always said you are not losing me. i'm not going anywhere. >> who knew my dad would become a woman at the same time i was becoming a man. >> juju chang, abc news, chicago. >> heck of a line. >> definitely. ben's girlfriend also has a transgender father. so, yeah, they're using each other for support. it just shows you after caitlyn jenner came out and revealed that picture, i think you are going to start seeing more of this. learning there are a lot of people that you know who are in