"How old are your daughters?" Fred asked a friend one day.

"The product of their ages is 36," replied his friend.

"You are not giving me enough information," protested Fred.

"The sum of their ages is the age of your oldest son."

"I still need more information."

"All right, then. I can tell you that the oldest daughter, who is at least a year older than the other two, is a very fine pianist."

"Ah! Now I know how old your daughters are."

What are the ages of Fred's friend's daughters?