TULSA, Oklahoma - The father and sister of Ethan Nichols testified on Wednesday in the murder trial of Darren Price.

Price is accused of robbing and killing Nichols and his girlfriend Carrisa Horton in Tulsa's Hicks Park in 2011.

Price's attorney says Jerard Davis, a man who's already pleaded guilty, did the robberies and murders.

In the courtroom, Ethan's sister and father talked about they learned he'd been murdered.

His sister started crying when she said she had to identify Ethan's wallet found at the murder scene and Ethan's father sobbed when he was asked to identify a picture of his son.

Both told the jury they frantically called and texted Ethan's phone after someone called and said Ethan hadn't shown up for work.

They both got responses, only to realize later Ethan and Carissa had been shot to death hours earlier.

When Ethan's father expressed how worried he was in a text, this is the text he got back from Ethan's phone:

"Nothing's wrong. I just woke up this morning and felt tired of life."

Ethan's dad said he was confused and frustrated, so texted back: "Something wrong with you and Carissa?"

The answer: "No, I just want to start over with everything. Me and her are moving away for like two weeks. We need a vacation."

Ethan's father testified none of this was like his son, but he did suggest his daughter cancel the missing person's report she'd filed.

She refused.

She got angry, thinking Ethan was being disrespectful to the family with his short, vague answers.

She sent this text: "I'm not calling them off until you give me some answers."

The reply: "Sorry, I really just don't want to talk."

She answered: "That doesn't cut it. How do I know this is even you if you're not talking."

It wasn't long after when Ethan's family learned the truth.

Police said Ethan's sister is a hero, because despite her grief, she continued to help police.

They asked her to send one final text to draw out the killers.

Saying she'd canceled the police report, she texted: "I have your check here and I know you're needing it. Do you want me to cash it like usual and get it to you?"

The reply: "Yeah."

Police say shortly after that, Price got into Ethan's car, which officers had under surveillance. Officers said not only was Price driving Ethan's car, but he had Ethan's cell phone in his pocket.

Price's attorney did not cross-examine Ethan's father or sister, but did say "I'm sorry."

Police officers testified about collecting evidence, including Ethan's wallet and surveillance video from the park.

On a courtroom TV, prosecutors showed pictures of dirt on Ethan and Carissa's knees.

A crime scene investigator testified it showed the two were kneeling when they were shot.

The investigator said when Carissa fell forward from the gunshot blast, she cut her lip and got dirt in her mouth.

Her family kept their heads down during that part and quietly wiped away tears.