This show has so many nicknames, the girls just within the family:

Kathy--Angel (Margaret's), Kitten (Jim's)

Betty--Princess (Jim's)

James Jr. - Bud, within and outside the family

Kitten and Princess...ugh

I am not sure how many choices there were back then. I know pixie was a popular nickname.

I forgot Bud's nickname for Betty -- Tallulah.

Betty was at her most annoying, snobbiest in that Country Cousin episode.

American Indian origin, and the meaning of Tallulah is "leaping water".www.thinkbabynames.com/meaning/0/Tallulah