The PlayStation All-Stars: Battle Royale team has been very careful to treat the game's many franchises with respect, said director Omar Kendall in an interview with Polygon. "We take this very seriously, and sometimes the IP holders know best, and obviously we want to present the characters in the best way for the developers and the fans," he said, after noting that Irrational creative director Ken Levine wrote the dialogue for the Big Daddy / Little Sister character. According to Kendall, Levine "wrote every line of script and dialogue" for the pair.
The same care went into every character, with each studio getting "complete, 100 percent approval" on its characters, he said. That includes characters owned by Sony studios, like Nathan Drake, the star of Naughty Dog's Uncharted series.
As for Levine's script, we're presuming it includes several instances of "Mr. Bubbles" and "MMMRRUUUNGGHHH!"