Rob and Michele Reiner's children are breaking their silence following the couple's killing.

The acclaimed "Princess Bride" director and his producer wife were found dead in their Southern California home on Sunday, Dec. 14. On Tuesday, prosecutors filed criminal charges against their son, Nick Reiner, who is accused of "fatally stabbing" his parents.

"Words cannot even begin to describe the unimaginable pain we are experiencing every moment of the day," Jake and Romy Reiner said in a statement to TMZ and People released Wednesday. "The horrific and devastating loss of our parents, Rob and Michele Reiner, is something that no one should ever experience. They weren't just our parents; they were our best friends."

USA TODAY has reached out to representatives for Rob, Michele, Romy and Jake Reiner for comment.

Rob and Michele Reiner deaths: Live updates