1860 US Census for LA lists the following individuals living in District 7, St. James Parish, LA:

Name: B Hymel
Age in 1860: 2
Birth Year: abt 1858
BirthPlace: St James
Gender: Female
Post Office: Vacherie Road
Household Members Age
Symphorien Tregre 80 (no occupation)
Valsin Hymel 27, farmer; also on 1870 US Census with a 53-yr-old white female B Hymel (his mother?) and 15 other Hymel family members.
Louis Hymel 10
C Hymel 6
Elmire Hymel 4
B Hymel 2
Amelia Lawrent 24

An individual by the name of H S Tregre is listed on 1860 US Slave Census in St James Parish, Right Bank Dist 7 with the following slaves:

2 Black Females and 2 Black Males, all age 40
1 Mulatto Male, age 35
1 Black Female and 1 Black Male, both age 30
1 Black Male, age 12; 2 Black Females, age 7 & 9

Apparently, Tregre owned the slaves and the Hymel family might have inherited them. On the 1870 US Census for this same Dist 7, there are several Tregre familymembers.