Little Johnny walked into his dad's bedroom one day only to catch him sitting on the side of his bed sliding a condom onto his dick in preparation of sex with his wife.
Johnny's father in attempt to hide his full erection with a condom on it bent over as if to look under the bed.
Little Johnny asked curiously, "Whatcha doing dad?"
His father quickly replied, "I thought I saw a rat go underneath the bed.
To which Little Johnny replied, "What ya gonna do, fuck him?"