Final answer:
In the book Wonder, August's father, Mr. Sieppe, gets mad when August cuts off his Padawan braid.
Step-by-step explanation:
In the book Wonder, August cuts off his Padawan braid, which angers his father, Mr. Sieppe. This event is described in the passage provided, where Mr. Sieppe reprimands August and threatens him with punishment. Cutting off the braid is seen as a disobedient act, hence the negative reaction from Mr. Sieppe.