The Rosenthals spend Father's Day like most families – with their dad.

"Here, Mark, have a fry," Robin Rosenthal told her husband on the holiday a few years ago, then tossed one in his direction. But Mark couldn't catch it. That's because Mark is dead.

OK, so, not exactly like most families.

Robin – sporting a tie-dye T-shirt and a condiment on her face – was throwing the fries on his grave. Her son Sam, 31, posted that now-viral video on TikTok in June 2021, where it has since steadily amassed 15.6 million views and 3.2 million likes.

"You can tell by what I was wearing I was not prepared for that," Robin says over a recent Zoom call with Sam and daughter Emma, 28. "To have that go viral like it has, I'm still super embarrassed about what I look like." But she's not super embarrassed about what they were up to.

The family visits Mark's grave regularly, and on important occasions and holidays. But they always make it fun. This past Father's Day, they brought a kiddie pool. In April, Sam brought his girlfriend to meet his dad and Robin got down on one knee and begged her to be her daughter-in-law.

"I can't get this kid to propose to her, so I don't know what I'm going to do ... I love her, and Mark would love her," Robin says. All the humor, of course, is tinged with haunting heartbreak. It's been 13 years, and these children never knew their dad as adults. "Now we are talking about the things that he's missing out on," Emma says.

People have long flocked to social media to grieve; some are sharing stories with their dead loved ones directly on social media. Grief experts welcome this type of public healing, for both the bereaved and those watching who may learn something in the process.

"What I love about it so much is that it normalizes grief, No. 1, but it also shows that grief is so much more than just crying and sadness and laying in your bed and not being able to get up," Gina Moffa, licensed clinical social worker and author of "Moving On Doesn't Mean Letting Go," previously told USA TODAY. "It shows that the relationship continues. It shows how a relationship continues, it shows that it doesn't all have to be sadness and upset and despair."

As Robin puts it, "Life is a gift. Mark's gift's over, but we still have ours, and we're going to make the most of it."

'We find humor'

Mark Rosenthal died of a heart attack more than 13 years ago. He had just turned 60.

"He just dropped dead," Robin said. "He went to the bathroom. I heard the pound on the floor. I got up. I screamed at Emma." Emma started CPR, which she learned from an episode of "The Office." At the hospital, the staff sent along a minister – the Rosenthals are Jewish – and he was holding their hands and praying to Jesus. They started laughing hysterically (how could they not?) even though Mark had died just hours before.

"There are moments of great sadness," Emma says. "But I think that we find humor in those moments too. It's not funny when when you're in it, but the the reflection is usually funny." Sam adds: "There's still waves. There's always waves."

Robin took a lesson from a relative and ran with it: "Until you come to the realization that (your loved one is) not coming back, it's hard to move forward."

It's "a lifelong process," Jessica MacNair, licensed professional counselor, previously told USA TODAY. "It's not prescriptive, it's not, five stages in order, you move through these, and then you reach the end. It's ongoing, it comes up in varying times. And, in fact, I mean, that's probably one of the main reasons that people come back to therapy."

'We're always throwing some sort of food'

Before the pandemic, Emma was living in Chicago getting her master's degree in comedy screenwriting, and Sam was living in Philadelphia performing stand-up while Robin was at home in Bucks County, Pennsylvania, the county's Recorder of Deeds.

When the pandemic hit, Emma and Sam moved back home. That's when the comedy trio came alive.

"We were just doing a puzzle one night, and I recorded a video of my mom ranting about the fact that this puzzle had 1,000 chickens and a worm, and we couldn't find the worm," Emma recalls.

"And they both have master degrees!" Robin interjects. "I mean, really, why couldn't these two find the worm?"

The posting took off from there. The videos don't all touch on grief, but "from day one, when we were filming, everything is just so real us," Emma says. "Our content is just slice of life."

Speaking of slices: Mark loved food, so they always bring it to the cemetery. Starbucks, M&Ms, french fries, you name it. "We're always throwing some sort of food, and it's not there when we go back," Emma says. "He's eating it," Robin jokes.

In case you missed:People are talking to their dead loved ones – and they can't stop laughing. It's a refreshing trend.

'People die but relationships don't'

How would Mark feel about the family's virality? He'd love it. "He wasn't good at speaking in front of groups, but he was funny, and we were a very, very close family," Robin says. "As you can tell, the three of us still are."

That closeness continued as they all grieved. He died at the end of October, and they joined a grief group for children who've lost parents or siblings before Thanksgiving. The programming included support for parents, too. One of Emma's favorite things was when someone in her group would be sharing something heartwarming, only to hear the parents laughing at something Robin said: "We'd be like, 'What are they talking about?' And then we'd get in the car, and she'd go, 'oh yeah, that was me. I made a joke.'"

"It fostered our way of helping people deal with grief," Robin adds. No matter how people are grieving on TikTok, one thing is clear, according to Moffa: "People die but relationships don't."

'It's OK to laugh with the tragedy'

Robin knows how critical their platform is. Even though everyone will go through tragedy, "everyone deals with it differently," she says. "And I've learned that if you don't deal with it up front, it's going to come back to bite you when you're older."

That's why she's kept Mark's memory alive.

"There has never been a moment where we haven't talked about our dad," Emma says. "Doing something fun, 'Dad would have loved this.' Bringing up memories from before, and doing those things now, sharing what we do online has really helped show people it's OK to talk about your loved one. It's OK to laugh about your loved one. It's OK to laugh with the tragedy."

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