Ned's old friend from law school, Mr. Nelson, has two sons: Eric and Wesley who are the same age as the twins and one year younger. Since he and his wife want to attend a conference in LA, Ned and Alice agree to watch his kids for the weekend. The twins actually can't wait to meet some new people and plan all the fun things they can do together. Jess is a little hesitant though because she doesn't really like hanging out with boys.
While hiding out in their fort in the woods, they hear their mom calling because the boys are there. They almost immediately start pulling pranks on the twins. Jessica freaks out when she realizes that her stuffed bear, the one she always sleeps with, is missing. After searching the whole house, the boys tell them that they stuck it in their parents' car and that the bear is now on a trip.
The guys also replace the sugar bowl with salt, which leads to Liz and Steven putting salt in their lemonade. To get back at them, the girls make a bunch of water balloons, hide upstairs, and then toss the balloons at them from the window. The guys get drenched just after drying off and changing clothes after a swim. Ned lectures the twins on how they need to be nice to their guests.
Eric and Wesley then put a bunch of bugs in the bathroom. They think all the bugs are fake until a grasshopper almost jumps on them. When they try to leave, the boys hold the door closed. Alice and Ned finally hear their screams and just roll their eyes at the situation. The twins get a lecture on how they shouldn't overreact and how boys will be boys.
What really sets them off is when they see Eric and Wesley playing in the living room. Apparently, Alice recently spent a lot of time and money on redecorating the room and made it a rule that no one can play there. You're right Alice, who actually lives in a living room? The boys keep goofing off and break her new vase. Alice lectures the twins and tells them they should have told the boys not to play there.
After stomping upstairs, the twins decide that their only choice is to run away. They pack some food, leave a note on the refrigerator, and run away to the fort. It doesn't take long before they run out of food, and both get scared by the sounds they hear outside. They finally hear their parents calling for them and decide to keep hiding for a bit, but then the boys find them.
Everyone compliments them on their awesome fort. Ned apologizes for not listening to them, and Alice says that she probably should have told the boys about the no playing in the living room rule. Gee, you think? The boys apologize too, and everyone gets along until their parents come home and Jessica gets her bear back.
*Steven is kind of funny because he moans about the house being full of babies and when the twins point out the boys are basically the same age as them, he says it proves his point.
*Alice makes lemonade but doesn't put any sugar in it and tells the kids to add as much as they want. Who does that??
*The twins' parents refuse to believe that the boys would lock them in the bathroom. You're right, there has to be another logical reason for your kids to scream bloody murder first thing in the morning.
*The note they leave is hysterical. It's pretty much, “we'll come back when you learn how to not be so mean to us.”
*They take two peanut butter and jelly sandwiches, some chocolate chip cookies, and two apples with them.
*So apparently, Ned and Alice do not know about the fort because they don't bother looking in there and are shocked by how cool it is. Way to be parents.