Louche kitty sweater! UK 10 US 6

This is a Louche sweater with adorable white kitty on it! UK size 10 usually equals US 6 but this was actually too small for me as a 6 (Poshmark purchase I was crushed didn't work!) I'd say it's a very small 6. Measurements lying flat are: Shoulder to shoulder is 14 " Chest pit to pit is 15" Length from shoulder is 21"