Haha yeah! I usually do a pass on Dipper/Mabels dialogue to try to make sure they feel like the characters I know for the most part. I never actually wrote out 10 actual commandments, but here’s a few rules I find myself going back to with the writers:
1) The kids LIKE each other. No matter how much they get on each other’s nerves, this never changes.
2) Mabel’s not stupid. She’s a ham! There’s a big difference. Mabel’s love of goofing off is a natural force of her personality, but she can still understand when people she cares about need help or are in danger. Don’t just make her a catchphrase machine. She really cares about the people around her. (Secret: Mabel’s secretly jealous that her brothers better academically than she is)
3) Dipper’s smart but he’s not a “WALKING CALCULATOR” There’s a lot of kids shows featuring a character who is “the brains.” You know the guy. Thick glasses, nasal voice, often starts every sentence with “According to my calculations!! SNORT!” Pretty much every kids show stereotype can be traced back to the BK Kids club. This one would be IQ: http://i.imgur.com/RAhYsI7.jpg
The point is, Dipper is better academically than Mabel, but he’s also able to laugh at himself. He’s a real kid. He has insecurities. He has things that he loves. I try not to pigeonhole these characters into “ONE TYPE” They lose their humanity if you do that. (Secret: Dipper’s secretly jealous that Mabel’s better socially than he is)
4) They’ve known each other forever. They should occasionally finish each other sentences, they should recognize when one of them is about to do something they always do, they should reference past inside jokes, they should get instantly angry at each other and then instantly make up, the way people who’ve known each other forever do.
5) They get more close in unfamiliar situations (because they need each other) and less close in familiar situations (because they dont as much) The entire summer is an unfamiliar situation, and its helping them bond.
6) Dipper wants to grow up too fast. Mabel doesn’t— Alex Hirsch (answering a question on the “10 commandments” of how Dipper and Mabel act around each other.”)