Joke of the day - Stupid question

A family is at the dinner table. The son asks the father, “Dad, how many kinds of boobs are there?” The father, surprised, answers, 

“Well, son, a woman goes through three phases. In her 20s, a woman’s breasts are like melons, round and firm. In her 30s and 40s, they are like pears, still nice, hanging a bit. After 50, they are like onions.” “Onions?” 

The son asks. “Yes. You see them and they make you cry.” 

This infuriated his wife and daughter. 

The daughter asks, 

“Mom, how many different kinds of willies are there?” 

The mother smiles and says, 

“Well, dear, a man goes through three phases also. In his 20s, his willy is like an oak tree, mighty and hard. In his 30s and 40s, it’s like a birch, flexible but reliable. After his 50s, it’s like a Christmas tree.” 

“A Christmas tree?” the daughter asks. 

“Yes, dead from the root up and the balls are just for decoration.”