The bad blood between the Shamrock family stretches back to the early days of mixed martial arts, but after over a decade of insults, petty disputes, and potential meetings in the ring, Ken Shamrock and adoptive brother Frank Shamrock recently made peace while filming for an undisclosed MMA project.

"We sat down and really had a conversation, and I think our relationship is back on track," Frank Shamrock told MMAFighting.com.

"We'll see where it goes. There's a business opportunity that got us sitting down for a couple of hours. It was really nice. It was very positive for both of us."

Frank and Ken, both UFC champions in their time, have thus far refused to reveal the project that reunited them.

Once teammates at the Lion's Den, the Shamrocks had a very public falling out in the late 90's and remained estranged while taking occasional potshots at one another through the media, very nearly coming to blows several times.

Over time, the brotherly quarrel evolved into one of the most infamous feuds within the sport. Yet after all those years of harboring ill will, Frank is now more than happy to be freed from such negativity.

"It feels good to put it behind you, to move on emotionally," Shamrock said. "Kind of have that feeling of rest, that's the best part for me. It's a new chapter, move on.

"It's been a long time."