Revealing mistake: Dickie is in the garage with Sam and sally, and throws down the farm toy. You can see a battery on the ground, yet it is still making noise.
Revealing mistake: When Dickie is learning how to ride a bike he falls down about four times and then hits a car and flies over it. As you watch him the camera goes to his point of view before he hits the car and you can see a dent where he had obviously hit before.
Revealing mistake: In the scene where David Spade and Scott Terra give a serenade on stilts, both characters rise up from behind a fence perfectly vertically. It's impossible to slowly rise upwards while on stilts the way the characters did. The way they rise, it's impossible for them to have simply had their knees bent and stood up straight. They must have been raised up on a machine.
Revealing mistake: In the "Child Stars" song at the end, before Leif Garrett sings, Dickie is playing guitar. His guitar has no strings.
Answer: Maybe Leif called Dickie, or vice-versa, without actually SEEING each other. Maybe it's not a weekly thing, maybe Leif is new to their poker group.