Fallon opened the show with a tribute to Gloria, explaining that he had canceled last week's tapings so he could be with his family.
"She was the best audience. She was the one I was always trying to make laugh," Fallon said of his mom. "She was such a fan of the show and everything I did."
A tearful Fallon thanked fans for their support during his grieving process.
"I feel so grateful to be able to do this every single night, and I'm very appreciative of all the support from all of you that my family received over the past week," he said. "We're gonna continue to work really hard to bring some light and some laughter into the world. Thank you for watching. Thank you for helping me and my family recover from this loss."
The host also shared a childhood memory before delivering a message to his mom.
"When we were little, my mom would walk us to the store — me and my sister — and we would hold hands. She would squeeze my hand three times and say, 'I love you.' And I would squeeze back, 'I love you, too,'" he said. "Last week, I was in the hospital and I grabbed her hand and I squeezed, 'I love you.' I just knew we were in trouble."
"Mom, I'll never stop trying to make you laugh," he said before squeezing his hand in the air three times and saying, "I love you."
Also during the show, Taylor Swift performed her song "New Year's Day," which contains the lyric, "You squeeze my hand three times in the back of the taxi."
Tonight Show writer and producer Mike DiCenzo later tweeted that Swift was not scheduled to perform, but accepted without hesitation when she was asked. He also wrote that Fallon had not told the story about his mom squeezing his hand, and no one had heard "New Year's Day," so when she sang that line, "We all lost it," he wrote.
"It was a beautiful coincidence in a beautiful performance," he added.
Photo Credit: YouTube / The Tonight Show Starring Jimmy Fallon