Grandpa has quite some hearing problems. So he decides to go to the doctor
for a check-up and asks his wife to come along. The doc looks in his ears
and performs all kinds of tests but he can't find anything wrong. 
"For further tests I would need a stool and urine sample from you". 
Grandpa doesn't understand a word, looks at his wife and yells "What does he want?". 
She yells back "He wants your underpants".