User blog comment:AustinDR/The Most Useless Characters/@comment-31563773-20170801181337

In Ronalda's case, they hadn't expanded on her character until they had her moving, which was a dumb ploy in the first place. But what all these characters share is that they haven't been fleshed out much since their first appearances. Luna could get a pass because she had her sexual orientation expanded more, but for Leni? Well, she's largely there to be the dumb one of the group and you can't really blame Luan for trying to make a pun every few seconds because she's aspiring to be the next Kevin Hart.

You could give Lily a pass though since you can't do much with a baby, unless the writers want to show her growing up and actually learning to speak more.