For nearly three decades, Mister Rogers showed us that a life full of compassion and kindness is the key to happiness. And when he passed away in 2003 at the age of 74, generations of children who grew up with their friendly neighbor mourned his loss.

But who was Fred Rogers off camera? His widow, Joanne, assures us all that he was exactly the same sweet man people remember since 1968 from the influential children's program, Mister Roger's Neighborhood.

Joanne shared with Kidscreen how music brought the two of them together.

After matriculating at Dartmouth, Fred Rogers realized he wanted to transfer because the Ivy League college didn't offer a music program. That's how Joanne and Fred first met at Rollins College in Winter Park, Florida.

Fred came for a visit to my college in my sophomore year. We met then, and he started at Rollins when I was in my junior year.

While we were [in school] together at Rollins, we became very good friends. When I graduated in 1950, I started a master's program at Florida State.

The 90-year-old widow has been making the rounds promoting the new documentary celebrating Mister Rogers, called Won't You Be My Neighbor. The film gives viewers a glimpse of the magic behind the show and insight into the man who was everyone's friend.

On the Today show, Joanne revealed how Fred proposed to her after he left Florida and moved to New York.

He wrote me a letter.

My last year at Florida State [graduate school], he wrote me a letter proposing marriage.

There's also the magic in numbers that people didn't know about. Joanne said the number 143 held a special significance for Fred.

He really wanted to remain at 143 [pounds] all of his life -- all of his adult life, I should say. Especially after he started swimming; he swam every day.

143 also signified his adoration for Joanne, based on the number of letters in each word of a special saying.

He was very pleased when he would get out of swimming, go and get on the scale: 143.

One was I, 4 was L-O-V-E, 3 was Y-O-U. He had enough love to go around.

Joanne said he was also very open with his feelings and always wore his heart on his sleeve.

In his young days, he was lively and full of fun.

But he talked about his feelings, and I could talk about my feelings to him and the things that bothered us, the things that we loved.

As he succumbed to stomach cancer in 2003, Joanne assured Fred that everyone was going to be okay. It made for a peaceful transition despite his pain.

There was a feeling of real relief when I could say to him, 'You know, we're going to be OK. We're going to be all right. The boys will be fine, and I'm going to try to be fine.'

So when he went, I could feel he went at peace and even with joy. I really feel he went with joy.

Even after his death, the emissary of goodwill continues to touch our hearts. Host Megyn Kelly asked what he would say in response to a divided America that "seemed to have taken a step away from love and kindness."

It would be about the children.

It would be about the immigrants who are having children taken. The children themselves.

This breaks my heart. And I know it breaks everyone's heart.

Won't You Be My Neighbor is currently in theaters and resonating with audiences as evidenced on the film review aggregator, Rotten Tomatoes, with a whopping "certified Fresh" Tomatometer score of 99% from critics and 97% from fans.

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