Stiles: Your Scott's younger sister, Scott approved of your guys relationship because he knew Stiles would never hurt you.
Liam: Lydia's younger cousin, Lydia didn't really like it because Liam had I.E.D but after she saw how he looks at you she changed her mind.
Scott: Liam's big sister, he approved after awhile because he soon grew to trust Scott.
Jackson: Derek's little sister, it took a lot of convincing but he soon accepted it.
Isaac: Stile's sister and surprisingly Stiles just accepted it.
Derek: Allison's cousin, when she was alive she approved and you like to think she still does.