Two mothers met in a street.  They started talking about their children.  "I have  three  sons," said the first mother.  "How old are they?"  asked the second.

"Well, it's easy to figure this out," replied the first mother.  "The  product  of their ages is equal to  36  and the  sum  of their ages is equal to the number of  windows  in the house  across  the street."

The second mother thought for a while and said, "What you've told me is  not sufficient  to solve your problem."    "Oh, yes, the  oldest  one is red-haired," replied the first mother and the second solved the problem.

What were the  ages  of the first mother's sons?