Rob Reiner and Michele Singer Reiner's two other children have spoken out for the first time as their brother, Nick Reiner, appeared in court to face charges for the murders of his parents. 

Jake and Romy Reiner released the following statement on Wednesday:

"Words cannot even begin to describe the unimaginable pain we are experiencing every moment of the day. 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.

"We are grateful for the outpouring of condolences, kindness, and support we have received not only from family and friends but people from all walks of life. We now ask for respect and privacy, for speculation to be tempered with compassion and humanity, and for our parents to be remembered for the incredible lives they lived and the love they gave."

Rob Reiner had another adopted child, Tracy Reiner, from his previous marriage to actress Penny Marshall. The two were together for 10 years beginning in 1971.

The "When Harry Met Sally..." director met Michele Singer, a photographer, while working on the romantic comedy. In a 2016 interview with AV Club, he said meeting her was what made him change the ending of the movie, to have Harry and Sally end up together.

The couple got married in 1989, the same year the film was released. They had three children together.

Their youngest, 28-year-old Romy Reiner, is a photographer and an artist.

Jake Reiner, 34, their eldest, was a news reporter in Texas and California, including at CBS Los Angeles, before he followed in his father's footsteps. He acted in a few TV shows and films, including "Being Charlie," which was directed by his father.

Nick Reiner was also credited in "Being Charlie" as a writer. The film, which told the story of a teenager struggling with drug addiction and rehab, was "loosely based on things Nick went through and his relationship to me and his mother," Rob Reiner said in a 2016 AOL interview alongside his son. "It was intense. It was difficult at times."

The 32-year-old has been charged with two counts of first-degree murder with special circumstances in the killing of his parents, who were found dead in their home over the weekend, according to Los Angeles County District Attorney Nathan Hochman. The DA said the charges carry a maximum sentence of life in prison without parole or the death penalty, but that his office hasn't decided which to pursue.

The district attorney's office said in a statement that Rob and Michele Reiner were stabbed to death. The Los Angeles County Medical Examiner confirmed Wednesday that their causes of death were "multiple sharp force injuries." It wasn't clear as of Wednesday morning when exactly the attack happened, or how long the couple had been dead before their bodies were discovered on Sunday. The day before, they had gone to a party at Conan O'Brien's, where Rob and Nick Reiner had a brief but loud argument, sources who were there told CBS News.

Nick Reiner has not entered a plea. He appeared in court on Wednesday and only said, "yes, your honor," to agree to the arraignment date. 

Police have not released details about evidence in the case, or any information about a possible motive or what led them to arrest Nick Reiner. 

Newly released video shows Nick Reiner inside a gas station convenience store hours after the killings and just moments before he was arrested on Sunday. Video from outside the store shows the LAPD arriving and arresting him. He did not resist arrest, according to police. 

He is now being held without bail in a jail in downtown Los Angeles.