Who are they?

That is my grandma.
She’s old and fat.
That is my grandpa,
in a grey hat.
This is my daddy.
He’s thin and tall.
This is my mummy.
She’s young and short.
This is my brother.
He’s thin and young.
That is my sister.
She’s short and fat.
And this is me.
I put a bell on the cat.