Garth Callaghan, 44, conquered two rounds of kidney cancer before being diagnosed with prostate cancer. His oncologist has told him he probably has an 8 percent change of surviving the next five years.

And with that in mind, Callaghan made a promise. Inspired by the group, Because I Said I Would, a nonprofit advocating for keeping promises, he made a commitment to continuing writing a note to be placed in his daughter’s lunch until she graduated from high school, even if he wasn’t around to write them.

“I thought, I can write out napkin notes ahead of time, and have them ready if I can’t fulfill my own promise if something bad happens,” he told Today.com. In total, it adds up to 826 napkin notes.

The tradition began when Emma was in third grade and her father first started slipping notes on napkins into her lunchbox. At first they were simple words or drawings, now they include his thoughts, encouragements, and inspirational quotes ranging from words by Gandhi and Dr. Seuss to Audrey Hepburn and Fred Rogers.

“This isn’t a story about cancer, because any parent at any time could be hit by a car or have a heart attack," he said. "This is really about leaving a legacy so that she can understand some of my life philosophies and how much I love her.”

From her perspective, Emma loves the tradition.

"I love napkin notes for a couple reasons, not just the obvious ones such as knowing my dad is thinking about me or learning a new quotes,” she said. “I love them because they remind me not to take things for granted.”

Callaghan has started a website and Facebook page to help other parents connect with their kids. He's also created an e-booklet that includes many of the messages. (Note to other parents: He doesn’t mind if you crib from his napkins.)

He plans to publish a second edition with all 826 of the promised notes.

“I wrote an epilogue to it,” he said. “It basically implies that I expect to be around long enough to write my grandkids napkin notes.”

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