Crystal Jackson and Britney Cosby

Authorities are investigating the deaths of a lesbian couple whose bodies were found next to a dumpster in Port Bolivar, Texas.

Family and friends of Crystal Jackson, 24, and her girlfriend 24-year-old Britney Cosby hope police are close to solving the murders.

Jackson, left, and Cosby had been together for 2 years.

Crystal Jackson and Britney Cosby

The bodies of the couple, who were originally from Houston, were found Friday morning next to a convenience store dumpster in Port Bolivar, ABC affiliate KTRK-TV reports.

The families are demanding answers.

“What did they do to you for you to kill my sister,” said Jackson’s sister, LeQuetia Jackson in a tearful interview with KTRK-TV.

Jackson’s father told KTRK-TV he last spoke with his daughter on Wednesday.

“I will never hear her voice again, and never thought that it would come my time to bury my child,” said Ivan Jackson.

He said Jackson worked as a security guard, while Cosby worked at Starbucks.

Both lived together at Cosby’s great grandmother’s home.

“I never heard from them anymore, and that night I didn’t hear from her,” said Cosby’s great grandmother, Annie Lee Cosby.

The family said the women were killed after they returned from Galveston where they attended Mardi Gras.

Cosby’s family members are also grieving.

“Just come forward, just to give us closure as a family. ‘Cause we need closure at this point,” said Cosby’s aunt, Ebony McDade.

“They didn’t have to die. Whatever it was, it was petty,” said family member Leonard Freeman.

Police didn’t reveal how the women were killed. They said only that Jackson and Cosby were killed “in different ways.”

LeQuetia Jackson said her sister was beaten to death.

Authorities believe they were killed elsewhere and their bodies were moved to the location where they were found.

Investigators are looking for Cosby’s vehicle, a silver 2006 Kia Sorrento with drive out paper tags.

Anyone with information about the murders or the stolen vehicle is asked to call the Galveston County Sheriff’s Office tip line at 866-248-8477.