I am hesitant to link this, because Prudhomme is apparently not an uncommon name in Louisiana, and Donna was certainly not an unusual name at the time this woman was born, but there is a well-documented woman from St. Landry Parish with this name who would be about this woman's age. If they are one and the same, the genetic research indicating relatives in this parish was spot-on. If they are not, I would still not be surprised to find that there is some familial relationship there. There is another Donna Prudhomme from Louisiana who is slightly older, with different parents, living in Shreveport in her teens.
The St. Landry Parish DP was on the honor roll many times and participated in Girl Scouts, before marrying in 1982.