When I got closer to investigate, I found that he had gotten an arm in each of the arm holes of this little doll vest. My guess is that it is one of the girls' American Girl doll vests or it could belong to a similar sized stuffed animal or baby doll. How he had gotten both arms in past his elbows I do not know. He did need help to get out and when he was finally free he asked me "Mom, why was this in my top drawer?"
Great question Little One!