You should be able to solve this...

No.9650732 ViewReplyOriginalReport
A boy and his big sister are sitting around
the kitchen table chatting.

"You know, Sis, if I took away two years from
my age and gave them to you, you'd be twice
my age, huh!"

"Well, why don't you just give me one more
on top of that? Then I'll be three times
your age."

So just how old is each sibling?