Yes, kids just say what they think, often for maximum hurt! For me it was 4 eyes (glasses wearer) and match stick ( no muscles! Maybe that's another reason why I think muscle on women is great!).
Funny thing is, when I joined the gym seeking to build some muscle in my 20's and rejoined again in my 40's, the trainers both gasped at how much I naturally went for when curling. I've always had powerful arms, but virtually no muscle, much to my dismay. Genetics, an overrated subject in my view!
What a great idea sending those pics! I bet you wish you were a fly on the wall when the envelope was opened!