Get us the unit info on the one cousin and hopefully we can track down the alumni groups.
For next of kin who had relatives killed in action during WWII you can write the Army for their Individual Deceased Personnel File (IDPF).
The IDPF will almost always establish his unit and give information on his burial. In many cases, it will also give valuable information about where and when he died, possibly including reports of the action in which he died. For men whose remains were never recovered or identified, extremely valuable records of the testimonies of his buddies are usually included, giving extraordinary information about the action, what happened to him, and when they last saw him.
Be sure to mention your relationship to the person who died and that you are requesting the records under the Freedom of Information Act. You cannot request records by phone.
Freedom of Information ACT (FOIA) Office Total Army Personnel Command ATTN: TAPC-PAO (FOIA) 200 Stovall Street Alexandria, VA 22332-040 Phone: (703) 325-9256 Phone:(703)-325-5300