An 80-years old gramps married a young 18 years old girl. Their first night
they spend in different bedrooms. Late at night the new wife hears knocking on
the door. It’s her husband.
– Honey, I’ve come to perform my husband’s duty.
They do it and he leaves. An hour later he’s back.
– Honey, I’ve come to perform my husband’s duty.
They do it again and then the girl says:
– But darling, you’ve already performed your duty an hour ago!
– Sorry, darling, I’ve got Alzheimer’s.