Try this, it works wonders!!:
Soak the clothes in Tri-Enzyme for however 5min-to however long depending on how bad it's set.. with cold-lukewarm water for baby clothes.
Then to be extra sure the smell is out, you can soak them overnight with a scoop of All-Fabric bleach just to be sure.
Then wash it with SA8 laundry detergent. (On warm)
I'm going to sound like a salesperson here.. but these products really do wonders. We had pillowcases that were discolored from "bodysoil" and we tried EVERYTHING to get it out with no luck. Finally I tried doing the above method.. and they are like new again! (They were red checked against a white background.. and it worked without bleeding the colors).
If you are interested in purchasing them, contact me and I can help you out. You can't find them in a store. It's kind of like Mary Kay.. you have to know someone who sells it. And I believe in the products so much that I do that as well.