A few times a season, The Big Bang Theory spin-off Young Sheldon does an episode that directly ties into the mothership show. Previously, we've seen the origin of the "Soft Kitty" song, the first time Sheldon said "bazinga," and, on the night of TBBT's series finale, Sheldon checked in with the young versions of all the Bangers. Thursday night's episode, "Pasadena," was the latest in the tradition, and it was especially sweet and nostalgic now that The Big Bang Theory is over. In the episode, Sheldon (Iain Armitage) visited the California Institute of Technology for the first time, and though he didn't know it yet, he got a glimpse of his future.

In the episode, Sheldon wanted to travel to Caltech — the institution where he researched theoretical physics on The Big Bang Theory — to attend a lecture given by his hero Stephen Hawking. In another bit of dramatic irony, he wanted to go because he didn't know if he would ever get a chance to see the brilliant British scientist again. Little does young Sheldon know that in the future, Stephen Hawking will be his friend and confidante. After much cajoling, he finally convinced his dad (Lance Barber) to take him.

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At the end of the episode, as they walked around the campus, they found themselves in a room that seemed familiar, but we couldn't be sure, because the camera was angled on the Coopers and not the room itself. "Imagine all the stimulating conversations that go on at these tables," Sheldon said.

"I bet," George Sr. said.

"I can see myself going here one day," said Sheldon.

"I think you'd fit right in," said George Sr.

And then the camera pulled out to reveal the cafeteria table grown-up Sheldon (Jim Parsons) always ate lunch at with Leonard (Johnny Galecki), Howard (Simon Helberg), and Raj (Kunal Nayyar) on The Big Bang Theory.

It was just a table, but it was a really cute callback to a place where we spent so much time over the course of The Big Bang Theory's run. And it was neat to see it in Young Sheldon's more cinematic single-cam style. If you're a Big Bang Theory fan, it surely made you a little verklempt to see that table again.

Young Sheldon airs Thursdays at 8/7c on CBS. The Big Bang Theory will be available to stream on HBO Max when it launches in April.

Iain Armitage, <em>Young Sheldon</em>Iain Armitage, Young Sheldon