(Because you're Batman! XD)

Actually, Michael would be Gia's brother-in-law; definition here "the brother of one's wife or husband" Meaning that T.P is Gia's mate (husband) in the feature and Micheal is T.P's brother.

ah........"hit my head* what a fool i am........not really

no ill save the day..do you anna know why ill save the day

well when gia is mates wth t.p then there family is linked so mucheal is giaas step brother and gia is hiis step sister

Hold on! I'll save the day! Michelangelo is T.P's brother, so that makes him Gia's brother-in-law when she and T.P become mates ^^

step brother? but her steop brother is brittany, ¿whats happen here!?

Micheal: Uh...hi? *he doesn't actually know her yet*

uh gia no thats his gias step brother

gia: hi,nice to meet my best friend

Micheal: 'Sup?

Hi, T.P's big brother!