Texas is just hours away from carrying out the country’s first execution since the Oklahoma execution of Clayton Lockett was botched in April. While the family of Houstonian Alejandra Rendon hopes it will go through and bring them closure, Robert Campbell’s lawyers are doing everything they can to keep him alive.

Campbell and his lawyers have asked the Fifth U.S. Circuit Court of Appeals to stop his execution based on concerns over where Texas got its pentobarbital, which is the drug that will be used tonight.

“There’s no way to substantiate the safety if the drug,” said Kristin Houle of the Texas Coalition to Abolish the Death Penalty.

Houle says Campbell is also arguing diminished mental capabilities.

“He is intellectually disabled and therefore should not be subject to execution,” Houle told KTRH.

Rendon's cousin, Houston lawyer Israel Santana, told KTRH he expected this.

“I’m not at all surprised. Being an attorney I saw what happened in Oklahoma and immediately wondered if it would impact here,” Santana said.

Santana says his family hasn't been able to get closure since Campbell killed his cousin in 1991.

“We loved my cousin dearly. We miss her dearly. Every time we see a picture of her, it hurts,” Santana explained.

But he’s not sure whether or not Campbell’s death will give his family piece.

“We’re hoping that it brings some kind of closure,” Santana stated.

All previous appeals by Campbell have been rejected.