I grew up watching Mister Rogers' Neighborhood, and odds are you did too.
The famous children's show presenter first invited the world to his neighborhood back in 1966, and his series is still playing in reruns to this day.
In fact, a new documentary is set to examine the life and work of "our neighbor."
That means now is the perfect time to remember Fred Rogers with some little-known facts about him.
1. He started from the bottom
Rogers studied music, then worked as a production assistant for NBC.
He later admitted that the advertising and merchandising for the network's children's shows made him uncomfortable.
So he left his job and became a puppeteer for a small station in Pittsburgh.
2. He stretched out his words for a reason
Someone told Rogers that there was a limit to how much his young viewers could adsorb.
Supposedly, 124 words a minute was the "correct pace," so the TV host made sure to speak slowly and clearly.
3. His first show wasn't about his neighborhood
Before Rogers became Mr. Rogers, he was just a puppeteer and voice actor for The Children's Corner.
His first leading role came after he moved to Canada, and starred in an early version of the show called Misterogers Neighborhood.
4. He wore sneakers for a practical reason
Rogers was a bit of a perfectionist, and every detail of his show had to be just right.
That included shoes that didn't make any noise as he walked across the set. That's why he wore those stylish sneakers.
5. He tackled scary subjects
Mr. Rogers would address some pretty scary things on his show.
There were episodes about divorce and natural disasters, but also things that were only scary to children.
That included getting a haircut, and "falling down the bathtub drain."
6. He helped save the VCR
Rogers believed that making his show accessible to as many children as possible was important.
In that spirit, he argued to keep VCRs legal and helped win a very important Supreme Court case about the technology in 1983.
7. His mother made all of his sweaters by hand
He called putting on his famous outfit a way of "saying hello" to his mother in every episode.
And they were part of his regular wardrobe, not just his TV character.
8. Mr. Rogers was just as nice in real life
He insisted on acting just the same on TV as he did in real life.
"One of the greatest gifts you can give anybody is the gift of your honest self," he said. "I also believe that kids can spot a phony a mile away."
9. His workout routine was surprisingly tough
Rogers never smoke, drank, or ate meat (he didn't want to "eat anything that had a mother").
To stay in shape, he swam laps in a pool every morning. His goal was to stay at exactly 143 pounds, no matter what.
10. He won a lot of awards (and deserved them all)
During his decades-long career, Rogers earned the Presidential Medal of Freedom, a Peabody award, three Emmys, and 40 honorary degrees.
Good luck holding back tears as you watch his impossibly sweet acceptance speech for a Lifetime Achievement Emmy.
11. He was a talented musician
His first calling before television was music, and Rogers would sometimes show off his skills on the piano.
He also wrote and performed the show's songs, including the classic theme.
12. Why did he always mention the fish?
In his book Dear Mr. Rogers, the TV host explained his strange habit of announcing when he was feeding the fish.
A blind five-year-old girl named Katie had written to Mr. Rogers, asking him to tell her he was feeding them so she wouldn't worry.
After that, Rogers always explained that he was feeding the fish.
13. He had fans in the animal kingdom
Like Robin Williams, Mr. Rogers was a favorite celebrity of Koko, the gorilla who uses sign language.
She made a guest appearance on his show and took off his shoes right away, since he did that at the start of every episode.
14. He broke a lot of boundaries
Mr. Rogers famously invited one of his neighbors, Officer Clemmons, to soak his feet in a pool with him.
The 1969 episode was highly controversial, because public segregation was a very recent memory.
It was Rogers's way of making a subtle statement that children and their parents could understand.
15. He gave the Smithsonian Museum a dud sweater
Remember: we told you he was a perfectionist.
When the museum asked for one of the TV host's iconic sweaters, he picked one that "had never looked good" on camera.
Did you learn something new about Mr. Rogers?