When choosing adjectives to describe a character, we can turn to the text and see what the author has to say about someone. What adjectives (descriptive words) does the author use to tell us about a character? We can look for clues about their personality, their physical appearance, their manners and their hobbies. Does the author say someone is tall, kind, busy, old, stinky, or impatient? These are just a few ways an author may describe a character.
We can also make our own judgments based on how the character acts in different situations. If someone likes to sleep or sit around even when there is work to be done, we might say they are lazy. If a person feels very frightened about what might happen during different situations in their day, we could say they are nervous.
I would describe Catherine as very patient. Her little brother David has autism spectrum disorder, and Catherine has to help remind him of rules for appropriate behavior. Even though Catherine is often left in charge of her brother and may have to remind him of the same rule over and over again, she stays calm and helps her brother.
I would also say that Catherine is creative or artistic. Catherine brings her sketchbook with her everywhere and loves to draw. She even offers to make some new word-pages to help her friend Jason communicate.
I hope this has been helpful.