My daughter has skinny arms, but many of her pajamas still feel too tight. They're a little looser than most pajamas, but because they're tapered, they fit better around the calves and ankles. My daughter LOVES them and says they are a pajama/housewear combo. Her average height is 8.5 years and we gave her 8-9 points. There is definitely room for growth and she could probably wear them next year but they don't feel too big or baggy. If only using as underwear, consider downsizing if you want it to be more form-fitting.
Thermajane Girl's Cozy and Comfy Thermal Underwear Long Johns Set with Fleece Lining
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