A mother and father dead. A son arrested. A community in shock.

Hollywood is reeling from the deaths of comedy legend Rob Reiner and his wife Michele Singer, after the two were found dead in their Los Angeles home Sunday. Their son Nick has been arrested as a suspect in their deaths, according to police.

When faced with such horrific tragedy, mental health experts say, all kinds of feelings can arise. Shock. Grief. Anger. Numbness. An event of this magnitude and family tragedies in general often leave people struggling to make sense of what happened and figuring out how to chart a path forward.

“It changes everything,” psychotherapist Stephanie Sarkis says, describing the Reiner tragedy as “utter loss” on multiple levels.

Rob Reiner and wife Michele Singer and son attend Teen Vogue’s Back-to-School Saturday kick-off event at The Grove on August 9, 2013 in Los Angeles.

There’s “the loss of who you thought this person was − the person that committed the act − and then also the loss of the victims and then the loss of the family unit,” she adds. “You don’t get closure from something like this.”

Rob Reiner and when a family suffers the unimaginable

Everyone grieves differently. Everyone responds to tragedy and trauma differently. And people’s reactions can be surprising.

Philip Lewis, a therapist who helps treat anxiety, anger and addiction, describes grief as like a fingerprint − we all do it in our own way and in our own time. That goes for the Reiners’ family and loved ones. But it also goes for their fans around the world, those that grew up watching “All in the Family” or “When Harry Met Sally,” and feel connected to the couple through their art.

Tragedy, Sarkis says, is also something that can change your view of people − both of the individuals in your life, as well as of humanity in general.

Who’s in Rob Reiner’s family? What to know about parents, wife, children 

The biggest question people often have in the wake of family tragedies, psychotherapist Marni Feuerman says, is, Why? It’s not something that usually has a neat and tidy answer.

“People try to make sense of these unspeakable tragedies, but often can’t,” she says. “There’s really no explanation.”

It’s something people around the world are experiencing, not just amid the Reiner news, but also in the wake of two other horrific, deadly events over the weekend: mass shootings at Brown University and at a Hanukkah celebration at Australia’s Bondi Beach.

“It’s a lot for people to process at once,” Sarkis says. “The unfairness of life is really hitting people, and that can be a really hard thing to have to live with.”

The toll of addiction

Another looming question over the Reiner case is Nick Reiner’s history of addiction and homelessness and how that might have factored into what happened Dec. 14.

Nick Reiner told People magazine in 2016 interview that he made his first visit to rehab at 15 and would return 17 times. He said he became homeless due to his refusal to return to rehab. His struggle with addiction became a point of artistic connection with his father, as the two co-wrote movie about it, called “Being Charlie.”

“It’s by far the most personal thing that I’ve ever done,” Rob Reiner told AOL Build in a May 2016 interview. “But the fact that we were dealing with things that Nick had gone through and how I had related to it and how his mother had related to it, it forced me to have to see more clearly and understand more deeply what Nick had gone through.”

Director Carl Reiner presents an award to his son, director Rob Reiner at AARP Magazine’s “10th Annual Movies For Grownups” on Feb. 7, 2011, in Beverly Hills, Calif.

Rob and his family at the premiere of “Rumor Has It” at the Grauman’s Chinese Theater on Dec. 15, 2005.

Romy, Rob and Michele at the Friar’s Club Entertainment Icon Award at The Ziegfeld Ballroom Nov. 12, 2018, in New York City.

See Hollywood icon Rob Reiner and his family through the years

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Director Carl Reiner presents an award to his son, director Rob Reiner at AARP Magazine’s “10th Annual Movies For Grownups” on Feb. 7, 2011, in Beverly Hills, Calif.

Psychologists say addiction and mental health can be fluid. They can take quick, sharp and unexpected turns. Sometimes, someone who seems to have made leaps and bounds can slip back suddenly. No one − not even celebrities − are exempt from this painful reality.

“Addiction can really tear families apart,” Sarkis says. “Sometimes you can do whatever you can to help the person, and they still may not be helped. You can do everything ‘the right way,’ and addiction may still be very present.”

When there’s nothing more that can be done to help someone, the end result can often be tragic.

“It very quickly evolves into an issue around the whole family system,” Feuerman says of addiction. “We know that often tragedy is sort of the end result at times when the issues just cannot get resolved.”