Start with what you know Elizabeth Durocher b: "abt" 1840 would have been 7 in 1847. The 1880 census says both Elizabeth and Richard were b: in Louisiana. Her son Gustave was b: when she was around 17. I found a death certificate for his daughter Louise Marie Tabb Loncon it says her father was Gustave Tabb and her mother was Georgina Bourlier she died in Adeline, , St. Mary, Louisiana. http://search.labs.familysearch.org/recordsearch/start.html#starthttp://search.labs.familysearch.org/recordsearch/start.html#start
1860 census St Mary, Louisiana has a Richard Tabbs b: "abt" 1848
a death certificate for Agnes Maxine Tabb married to Richard Tabb could be a son of Richard Tabb and Elizabeth?