It has his namesewn in it and also written on the label. Whoever had it was using it, as it smelled of fabric conditioner. There is a child with the same first name as DS2 (different spelling) but his last name is completely different to ours.
The missing jumper was given to DS2 by a classmate who said "Here's your jumper I found it in next doors classroom".
SO the person who had it intially must have taken it again, what can I do? I don't know this child or his parents - assuming it is the one with the same name, it could be someone else completely. But why would you go around wearing a sweatshirt with another child's name on it?