Have Mercy! John Stamos Posts Sideburn-Heavy Pic from 'Fuller House' Set

Have mercy! Uncle Jesse has returned!
John Stamos posted a photo from the set of Fuller House, the Netflix reboot he's not only acting in but producing as well.
The Instagram snap proved that even though he's also starring in a sitcom titled Grandfathered, Stamos has barely aged a day since Full House premiered in 1987. (Yes, that's almost 30 years ago. No, we don't know how that's possible either.)
"And we're back!" he wrote. "Same sideburns -- different decade."

Even more nostalgia-inducing was the tweet Stamos sent a few hours later, writing he was "home again after 25 years."
All of the '80s feelings are flooding back right now!
Just yesterday, the 51-year-old actor said he was, well, "back," after a month-long stint in rehab.
Now that's how you return in fighting shape!
Earlier this month, ET caught up with Stamos' co-star Candace Cameron Bure. Find out what she had to say about her TV uncle's rehab stint in the video below.