The Annoying Inlaws gave Mr. I a t-shirt for Christmas. Their house now has such a mould problem that fabrics that are just sit in the house pick up the smell. (They gave one of the nieces some clothing that also stinks so I don't believe the problem originated in the shirt..)

Anybody know a sure fire way to get rid of it? I have seen vinegar, borax and baking/washing soda suggested (seperately) online. I am leaning towards vinegar, because I know it can kill mould and I’m hoping it will nuke any spores in the shirt. We’re both allergic to mould and want to get it done in one fell swoop.