By Aja Hoggatt
June 13, 2018 at 04:26 PM EDT

Joanne Rogers, widow of beloved children’s television personality Fred Rogers, stopped by The Tonight Show Starring Jimmy Fallon to spread one simple message: love.

While promoting the new documentary Won’t You Be My Neighbor?, about the life and career of Mister Rogers, the 90-year-old Mrs. Rogers shared the importance of the number 143 to Fred. Not only was it the weight that he remained all his adult life — quite an impressive feat — but it was a number that had a very special meaning to the Mister Rogers’ Neighborhood star. Joanne revealed that each number stood for a word of the same length, spelling out ‘I love you.’

REVIEW: The Mr. Rogers doc Won’t You Be My Neighbor? is the film we need right now

As the crowd reacted with a harmony of awws, Joanne went on to share how the couple, who was married for 50 years, met, telling Jimmy that when she met Fred in college, she knew right away he was different. “He would talk about his feelings and I could talk about my feelings to him,” Joanne expressed lovingly.

She also shared why her late husband, who was an ordained minister, was so passionate about using his platform to tackle big issues such as divorce, war, death, and racism.

“The [black] policeman on the program, Officer Clemmons…came by on a hot day, and Fred was out soaking his feet in a small kiddie pool,” Joanne shared, explaining how, to take a stand against the racism of the time, Fred invited a police officer to share a kiddie pool with him and allowed him to use his towel.

RELATED: Remembering Mr. Rogers, a true-life ‘helper’ when the world still needs one

As the segment came to a close, Fallon wrote “243” on a piece of paper, telling Mrs. Rogers it stood for, ‘we love you.’

Watch the videos above for more. The Tonight Show Starring Jimmy Fallon airs weeknights at 11:35 p.m. ET on NBC.