BoJack Horseman Season 4: 12 Biggest WTF Moments
2. Hollyhock Is BoJack's Sister...
When she first arrives to his home she causes quite a confusion. The girl thinks that she's BoJack's daughter, but already has eight dads, so her only reason to spend time with him is to get to know who's her mother.
The two try to learn about each other and BoJack really does his best to mature, and turn into a father-figure. When going through his mother's papers, BoJack finds out that he was in the wrong the whole time - Hollyhock is actually his sister.
Once he learns about it he's not relieved, because through this season he was trying to embrace the role of the father, even though he didn't handle it properly. He wasn't a particularly good dad and Hollyhock didn't need him in that role anyway.
As an older brother he'll have less responsibility and will be able to bond with the girl more freely, without building authority and other stuff that dads normally do.