Franklin the Turtle and Bear are heading to their cool-io tree fort when Harriet and Beatrice, their younger sisters, try to tag along. Though Franklin and Bear tell the girls they can't come, their mothers have a different idea. "But we were going to put our stuff in the tree fort," Franklin says. "There will still be time for that," says Mrs. Turtle. "Right now, you need to find something to do with your sisters --- something safe. That means on...