Here's how it works....
Step one: You have everyone weigh themselves before the big dinner. Make sure to record the weights of everyone.
Step two: Gorge, eat and drink as much as possible.
Step three: The weigh out! Re- weigh everyone.
Step four: Subtract the the first weight from the last to see the gain. This can be fun for the whole family, don't forget about grandma!
Make it a family tradition. I think the record so far is just over five pounds! Good luck and remember liquids carry a punch in the weight department.
Cheers and happy holidays. S.