Family reunion

[Big N' Blue]

There was a family gathering, with all generations around the table .
Mischievous teenagers put a Viagra tablet into Grandpa's drink, and after a while, Grandpa excused himself because he had to go to the bathroom .
When he returned , however, his trousers are wet all over .
'What happened, Grandpa?' asked his concerned children.
'Well, ' he answered, 'I don't really know. I had to go to the
bathroom; so I took it out and started to pee, but then, I realized that it wasn't mine, so I put it back !'