Ryan O'Neal's Grandson Sean McEnroe on 'Miraculous Moment' of Reuniting Family: 'It's a Huge Deal'

Ryan O'Neal's Grandson Sean McEnroe on 'Miraculous Moment' of Reuniting Family: 'It's a Huge Deal'

Ryan O'Neal Reunites with Daughter Tatum O'Neal and Grandkids After 'Years of Hardship'

Ryan and Tatum O'Neal have been public about their fallouts and reconciliations throughout their fractured relationship

Ryan O’Neal’s grandson, Sean McEnroe, is opening up to PEOPLE about reuniting his family for an unforgettable family photo.

McEnroe, 32, tells PEOPLE exclusively he shared the viral family photo on Instagram to capture an “extremely magical, kind of miraculous moment.”

On Sunday, McEnroe posted a family photo of himself with his mother, Tatum O'Neal, 56, his grandfather, 79, and his siblings, Kevin, 34, and Emily, 29.

In his caption, he revealed it was the first time the family had gathered together in 17 years. (Missing from the family photo is Griffin, the son of Ryan and brother to Tatum, as well as his sons Patrick and Redmond O'Neal.)

The artist son of Tatum and John McEnroe says he “actually did not expect” the worldwide reaction the photo has received.

“There are so many people who have been following this family saga literally for like 50 years, 40 years. At a time where there’s so little hope right now and people are really scared, really overwhelmed, and really having a hard time having faith that things are going to be better, there’s this family and if anyone knows this family, they know that this is probably the last family that will ever reconcile,” says McEnroe.

Sean McEnroe/ Instagram The O'Neals and McEnroe's

He adds, “It really was an ‘anything is possible’ moment.”

Describing his family, McEnroe says, “It’s really rare to have a family have this much chaos and drama over such a long span, and I think that’s actually the thing most families can relate to. That really kind of fractured, scarred family that’s having a very hard time reconciling and forging a good relationship later in life.”

Sharing his family’s photo is “a huge deal” to McEnroe “because the people who really know this story know, ‘Oh my God, I really thought that would never happen.’”

McEnroe's caption in the family photo read, "This is one of the most memorable photos of my life. The last time we were all together was at the 30-year Paper Moon Anniversary in 2003. I could cry tears of gratitude that everyone in this photo is still alive and that we were all able to come together again after so many years of hardship. The entire West Coast is burning, but if the O’Neals can reconcile, truly anything is possible."

Sean McEnroe Sean McEnroe

RELATED: Finding Forgiveness — Tatum O’Neal’s Family Drama

Ryan and Tatum, who's been open about her battle with rheumatoid arthritis in recent years, famously starred together in 1973's Paper Moon, which made Tatum the youngest person to win an Academy Award at just 10 years old.

Their fractured relationship since has often been talked about publicly. In 2004, Tatum detailed her dysfunctional relationship with her father in her searing autobiography A Paper Life.

After a bitter 20-year estrangement, Ryan told PEOPLE Farrah Fawcett’s death in 2009 played “a very big role” in their reconciliation. Fawcett and Ryan, who share son, Redmond, never married. They split in 1997 and announced they would jointly raise their son. They reunited in 2001 after Ryan was diagnosed with leukemia, and Fawcett took care of him.

“She brought us back together,” Tatum said in 2010. She also revealed it was her father who extended the olive branch.

“He told me he’s sorry. He’s all I have in terms of family, and I needed him in my life,” she shared at the time. “My dad was absolutely everything to me.”

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