TULSA, Oklahoma - Robert Bever testified in his brother Michael’s murder trial Friday. 

Michael is charged with stabbing to death five members of his family in 2015 and trying to kill a sister.

Robert Bever is already serving five sentences of life without parole and one life sentence for the crimes.

Robert was on the stand all day in defense for his brother.

He started his testimony in a composed manner but became visibly upset when he was shown a photo of a hatchet found at the scene. At that point, he began breathing heavily and burst into tears.

"I don't know what I was thinking," he said.

Robert said looking back, it's unfortunate this plan came to fruition. He said for a long time, the plan wasn't real; it was just something he thought about to "make himself feel better."

He's 100% trying to take the fall for these crimes, saying multiple times on the witness stand that he committed the murders.

When Michael's attorney asked Robert if he saw Michael stab or attack anyone, he said he didn't. Robert said he didn't know if he ever saw Michael holding a knife. 

This of course directly contradicts Michael’s confession seen Thursday when he admitted to police multiple times that he stabbed his mother April, and his little brother Christopher. 

This also contradicts Robert’s written statement he gave to police hours after the murders. 

In that statement, he said "we" planned to kill the family more than once. 

This has been a graphic afternoon, with Robert describing in detail how the attack started and ended. 

Robert said when he first attacked the surviving sister, Michael said "what are you doing?!" and even threatened to call 911. 

Robert said in his journal, he created a "Robert Bever" character who was cold-blooded, and ruthless saying he "flipped the switch" into this character so he wouldn't think too much about what he was doing.

Robert said Michael did help him trick the three little ones into opening their locked doors but said he's ultimately the one that killed their siblings. 

Michael's attorney confirmed that Robert has tattoos on both of his hands. One says LWOPx5, referencing his 5 life without parole sentences. The other one just spells out the word “Five” for his five family members who were killed. 

Listening to Robert’s firsthand account Friday afternoon was surreal and a hard day for the jury and everyone involved. 

Robert admitted he wanted to be famous and talked at length about how his father was abusive. But at this point, there still no true motive behind why the brother's planned an attack on their entire family. 

Now, the question for prosecutors is to find out whether Robert’s account of events in court Friday is true, or not. 

“We weren't really sure what we were going to get. But I knew after meeting with Robert that he would be authentic with the truth, whatever that is to him. I think that's what we were seeing in there,” said Michael Attorney Corbin Brewster.  

“I think anybody sitting in the gallery would say it's hard to even fathom what's coming out of that person's mouth. So, what we do is do our job and start challenging whether there's truth to what he's saying or not,” said Tulsa County DA Steve Kunzweiler.   

Robert talked about wanting to be famous, saying he wanted to create a higher body count than Columbine and the Aurora movie theater shooting.

He's not finished yet. Robert will be back on Monday with even more to say.