Great new pick up! Yes, it does look more like a Spotted. For all I know, it could be a children's x spotted cross. For sure not a pure chilreni though.
If it was being fed only 1 mouse pink every two weeks that would explain the tiny size. My Yearlings are around 50-70 grams, with my smallest being 30something. Granted, I definitely feed more on the conservative side. My bigger yearlings are getting 2 fuzzies or a small hopper every 6 days, and my younger ones are on a fuzzy every 6 days.
With a regular feeding schedule, he should catch up pretty easily
EDIT: When I get home later this evening, I can take comparison pictures of my Children's vs (Cape York) Spotted's vs Anthills for you.