John Stamos extends open invite to Olsen Twins: 'They're always welcome' on 'Fuller House'

John Stamos sat down with Matt Lauer on "Today" on Monday to talk about his two new shows, "Grandfathered"and the upcoming "Fuller House." But first he opened up about his recent stint in rehab this summer.

Lauer began by asking Stamos if there was any particular episode that prompted his decision to get help.

"Well, I lost my mother last year and she was the love of my life," replied Stamos. "And so obviously it was a very difficult time for me. I had some time off and I had a decision to make and I'm so glad I did it."

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Stamos also extended an invite to the Olsen twins -- the only original cast members who have chosen not to return to the Full House reunion show.

"Might they pull off one of the great surprises and make an appearance?" asked Lauer.

"They're fully welcome," Stamos said. "Any time. There was a lot of miscommunication in the press and stuff. But I understood why they didn't want to come back. They have big lives. They haven't acted in a while. But I love them dearly and they're always welcome on our show."

See John Stamos through the years:

Aside from the serious questions, Stamos and Lauer also engaged in a bit of hand-to-face combat after Stamos mentioned slapping a castmember on Grandfathered.

Lauer asked, "Is it harder to be the guy who slaps someone or the guy who gets slapped, knowing it's coming?"

"You tell me," said Stamos standing up for the test.

After they took turns slapping one another, with Lauer trying -; unconvincingly -; not to wince, Stamos referred to another fight Lauer got himself into on the show: "That was sort of like you and Tom Cruise. It was the same vibe."

"It never quite crossed that line," Lauer laughed.

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