"A necessary condition" joke
There were three little boys visiting their grandparents. The oldest came out and asked his grandpa, "Can you make a sound like a frog, Grandpappy? Grandpa (being in a kind of ill mood) responds, "No, I don't really want to make the sound of a frog now." So, the second little boy comes out and asks his grandfather, "Willyou please make a sound like a frog?" Grandpa again says, "No, not now. I don't really want to do that. I'm in a grumpy mood. Maybe later." Then the third little boy comes out and says, "Grandpa, oh please... Please, please will you make a sound like a frog?" "Why do all of you boys want me to make a sound like a frog?" Grandpa asked. The little boy replied with a hopeful face, "Well, Mom said that whenyou croak we get to go to Disney World!"
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