Son's Birthday

young boy's 15th b'day is coming up.
he asks his dad for a bike,
his dad replies "Can your d**k touch your a*&e"
"No", he replies.
"well, sorry I can't buy you a bike then" says the father.

on the day b4 his 16th b'day the young boy asks his dad once more for a bike.
"Can your d**k touch your a*&e" says his dad.
"almost", he replies.
"well, in that case...NO" says the father.

On the eve of his 17th he repeats the question, once again his dad replies:
"Can your d**k touch your a*&e?"
"Yes, dad it can", says the boy growing more and more impatient.

His father replies:

"well, in that case...GO FK URSELF"