John, according to pension applications, my gr-gr-grandfather George Fritzinger served with the 3rd Ohio infantry, arriving in Matamoros in August 1846. He indicates he marched with his regiment to Buena Vista sometime after his arrival in Matamoros, but does not mention the actual battle. The regiment marched back to Matamoros in 1847, after some time at Camargo, and mustered out in New Orleans in June 1847. I have also been trying to trace William H. Stouffer, who was 19 as George was, served in the 3rd Ohio, and mustered in at the same time from Wayne County OH, as did George. I have not found further mention of him in regard to the war, and have no idea if he died there or was wounded or ill. George's pension also makes no mention of any harm he may have suffered. If you have any information on William, or George's service, I'd love to hear about it. If you want anything further from me in regard to George Fritzinger, please let me know. Thanks.