If the whole bird is going to be cooked the night before, it should be cut into small pieces, stored in a shallow pan, and cooled thoroughly. Grandma may have cooked a turkey slowly overnight at a low temperature, but probably didn't realize setting the oven below 325 degrees doesn't kill the bacteria. Cross-contamination is always a concern when it comes to food preparation. Use separate utensils, cutting boards, and counter space for the raw products you handle. Wash your hands thoroughly after handling raw poultry.
Dinner is served.
Rarely is all the food consumed. Resist the temptation to get up from the table and let everything else sit. Leftovers should be dealt with quickly. Letting the food stay on the table for more than two hours after serving is asking for trouble. That means the turkey too.