Not, your normal American Family, at all.

Does your Normal American Family, Drink Blood?
Didn't think so.
Does your Normal American Family Go EXTREMELY fast?
Nope.
Is your Normal American Family So strong, that they can pull an extremeley huge root out of the ground with 1 hand?
No way.
Does your Normal American Family's skin shine like diomands in the sunlight?
Um, no.
Does your Normal American Family's eyes change differant colors form gold, to just plane black?
That would be just PLAIN creepy!
Does your Normal American Family jump and climb things thst can be 200 FT. tall!
Noooo!

Not eveyone is your " Normal American Family," Trust me.
Espeacially The CULLENS