(#6) Who is she?
She's his aunt.
(#2) Who's he?
He's her cousin.
(#1) Who are they?
They're her parents.
(#5) Who is he?
He's his uncle.
(#4) Who are they?
They're his grandparents.
(#1) Who are they?
They're her parents.
(#3) Who's she?
She's her cousin.