Oh Ellie, that's great! What a big step for her (and a happy day for you).
On what basis do you call 5'4" and 122 lbs. "perfect"--I mean, is there a set of standards you are using? Does it vary for a grown woman v. a teenage girl? I get so many comments about my weight now, and I can see that folks bring their baggage to the table--they range from "Wow, you look so great, tell me how you did it" (Answer: "Uh, my husband left me? Why don't you try it--works great!" ) to "You're too skinny, GBO, don't lose another pound...." I'm not really sure what to say to that ("Yeah, uh, I'll try to move this crisis along so I can get back to normal activities...."). But at the moment I'm about the same H/W as your daughter so I am curious what the experts have to say.....