"You know you're old when your walker has an air bag."

An attractive young girl, chaperoned by an ugly old lady, entered the doctor's office.
"We have come for an examination," said the young girl.
"Alright," said the doctor. "Go behind that curtain and take your clothes off."
"No, not me," said the girl. "it's my old aunt here."
"Very well," said the doctor. "Madam, stick out your tongue."