Jamie-Lynn Sigler Reveals the Heartbreaking Moment She Learned Her On-Screen Dad James Gandolfini Had Died

The Sopranos star Gandolfini died of a heart attack in 2013

James Gandolfini‘s unexpected death stunned Hollywood — and it was especially emotional for his fellow Sopranos alums.

In an exclusive sneak peek at this week’s Oprah: Where Are They Now?, Jamie-Lynn Sigler, who played the actor’s on-screen daughter on the hit HBO show for eight years, opens up about his passing — and the moment she found out about the heartbreaking news.

“Our cast was very much like a family,” says Sigler, 35. “James Gandolfini was one of the most humble human beings I’ve ever met, but also just one of the most powerful presences I’ve ever been around. He didn’t even realize, I think, the strength and light that he brought into every room that he walked into.”

Gandolfini was found dead in his Rome hotel room after suffering a heart attack at age 51 in June 2013.

“I was here, in this room,” says Sigler, explaining that she got the phone call from Vince Curatola, who played Johnny “Sack” Sacramoni. “He said: ‘All of us were confused as to who should call you because we know you’re pregnant … but Jim’s gone.”

Jeff Kravitz/FilmMagic

“I just didn’t have words — I still don’t,” says the actress, tearing up. “It’s just such a shock — we’d all seen him three months before, so it was confusing and sad. Not much was said, it was just a lot of crying.”

HBO arranged for a private plane to bring the cast members that lived in California to New York for his funeral.

“It was surreal, because how many times had we done funeral scenes as a cast?” recalls Sigler. “And to lay to rest our leader — he was the sun and we were the planets all around him. So the whole Sopranos life sort of came to an end at that moment.”

Oprah: Where Are They Now? airs Saturdays (10 p.m. ET) on OWN.