Their bodies were found last week dumped behind a business in Port Bolivar. On Friday, authorities spent time searching two locations for more evidence, including the suspect's home.
Galveston County investigators have been at a house on Howcher Street most of the day. They've been questioning relatives and collecting evidence from what some family members describe as a disturbing murder scene.
"Right now I hate him, I'm very angry with him. I want him to suffer, I want him to feel the pain that I have felt," grieving mom LaRonda McDonald said.
McDonald is blasting 46-year-old James Larry Cosby after he was arrested this week on charges linked to the murder of their daughter, Britney Cosby, and her girlfriend, Crystal Jackson.
"She said he didn't like the idea of her being gay, that he always threw it in her face," she said.
Britney Cosby and Jackson's bodies were found dumped behind a grocery store on Bolivar Peninsula on March 7. But on Friday, Galveston County investigators returned to a house on Houston's south side, which the young couple shared with James Cosby.
Detectives and the victims' supporters believe it's where Jackson was shot and Britney Cosby was beaten to death.
"Blood was all on the walls, all on the speakers -- on the sofa," community activist Quanell X said.
Family members say there have been heated fights between Britney Cosby and her father, a convicted rapist who's also been arrested in the past on assault and weapons charges.
"As us being parents, how could you just take your own child out of this world? I really hate him, I want him to suffer right now," McDonald said.
As Cosby sits in jail on two counts of tampering with evidence, detectives are also checking parts of south Houston, where some of the victim's personal belongings were found.
They're still hoping to find the couple's 2006 Kia Sorento, which is still missing, or clues into the person of interest who remains at large.
As this investigation continues, family members say the victim's funeral is scheduled for Saturday.
Anyone with information is asked to contact the Sheriff's Office TIPLINE at 866-248-8477 or Galveston County Crimestoppers at 409-763-8477.
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