Board Thread:General Discussion/@comment-11016223-20130904052318/@comment-24463671-20140125193052

I'm just going to say this and put an end to this debate.

Karai is not biologically related to Leo, Donnie, Raph, and Mikey for obvious reasons.

But they are her father's adoptive sons. Even though they are not biologically related they ARE technically her brothers (adoptive brothers).