Kate is the only daughter of the McReary siblings. She is often described as the bratty, sassy one of the group. She also appears to be quite mature (and tall) for her age, with her attitude being more around a teenager level rather than a second grader level. Although this appears to be odd in the original series, it fits slightly better in The Next Chapter as Kate is now 10 years old and in fifth grade.
Although there is not exactly an equivalent of Kate in the high school group, Aaron Velazco could be seen as the substitute for Kate, as both characters feel that they are superior compared to others.
A name in navy indicates a returning character from the original series. A name in teal indicates a new character introduced in this series. A name in italics indicates a character that will not make frequent appearances.