strange smells in my sons room
I'd call somebody out to investigate.  While a question like this may be off topic here; because we can't smell through the internet, your sons symptoms are quite alarming. If it smells like rotten eggs, it could be a natural gas leak, and your son is being gassed while he sleeps. It could also be sewer gas, which also is not healthy to breath.  

Since this issue is affecting the health of your son, you should take more action than asking a bunch of nincompoops on the internet. A local fire department has the equipment to test for gas leaks, and are more than willing to investigate for you. As testing for a gas leak, is much easier than putting out the fire it could lead to.