Board Thread:Legitimate Canon Questions/@comment-41.71.155.201-20140407133959/@comment-13965604-20140418194328

As we don't know yet the explanation for why Isaac leaves, we can't really rule out the possibility that he's still pack, even if he's not present.

The hospital scene implies pretty heavily that Derek is Pack, even if it's one of those things that nobody ever really talks about.

She may be a werecoyote, but at least one parent is an actual werewolf, so she might qualify. We just don't know.

Neither of the twins were ever Pack, so they can't be counted.