Okay, here's another thought. I found someone's Valega family tree on Ancestry with a photo of his son's headstone, which states that he was a PFC in Troop A 1st Regiment of the Louisiana Cavalry in the Civil War. I checked the State Archives' Confederate Pension database here:
http://www400.sos.louisiana.gov/archives/gen/cpa-alpha.htm

There are 2 records for him and 2 for his wife. I don't have personal experience with Confederate pension records, but when my great-great grandmother applied for her husband's Union pension, she had to supply quite a bit of documentation. It's worth looking into.

By the way, Nicholas (the son), was married to Marie Patricia Doize in New Orleans in January of 1880. If you want to order his marriage license from the state archives, tell them his name and give them this information: Orleans Parish Marriage Records, 1880, Volume 7, Page 106. According to his obituary which ran in the 3/10/1904 New Orleans paper, Patricia (as she was called) was his second wife and was a native of New Orleans.