Diana Dayton Masland

Diana "Bonnie" Masland (née Dayton) passed away peacefully with the help of a caring and compassionate hospice team on January 26, 2026, in Naples, Florida after suffering a stroke several days before. She was surrounded by love.

Bonnie was born to James and Ethel Dayton and was one of three children, alongside her siblings Bill and Babe. She grew up in Litchfield, Connecticut, where she demonstrated an early commitment to hard work and service, helping neighboring farmers care for and milk their cows. She later attended Abington Friends School in Philadelphia. She excelled both academically and athletically, particularly in basketball, field hockey and tennis.

She later married James G. Masland Jr., and together they raised three sons—James, Jonathan, and Michael—in Philadelphia.

Bonnie possessed a strong work ethic paired with a deep commitment to helping others. She earned a PhD in psychology from Temple University and went on to practice as a clinical psychologist for 25 years. Her work focused primarily on supporting individuals who had experienced childhood trauma. Bonnie had a rare ability to listen deeply, meet people with empathy, and help them find constructive and meaningful paths forward.

In the early-1990s, Bonnie met and married David Fish, the Head Coach of Men's Tennis at Harvard. They made their home in Newton, Massachusetts, and shared a love of biking adventures that took them to places as varied as the Blue Ridge Mountains in North Carolina, the hills of Santa Barbara, New England and upstate New York. Bonnie loved being active and adventurous, enjoying hiking, tennis, squash and travel with Dave.

After retiring from psychotherapy, Bonnie played a key role in transforming the Harvard Summer Tennis Camp into a thriving program. She cherished hiring and mentoring the young people who worked at the camp.

In later years, Bonnie found great joy in spending time with her grandchildren— Alina, JJ, Jonah, Jack, Elizabeth, Mary, Carter, and Owen.

Bonnie was an avid and intrepid traveler from early on. She studied abroad in Sweden, took many wonderful trips with Dave and as recently as October, the two of them traveled to Croatia for the ITF World Team Championships, an experience they both dearly treasured. She was equally content at home, where she tended her beautiful flower garden and beehive.

Bonnie is survived by her husband, her two sons James (Nathalie), Jonathan (Monica), her daughter-in-law Katie, and Dave's two children Alex (Amara) and Ashley (Greg), her brother Bill (Wendy), her sister-in-law Marcia (Brian) and brother-in-law Bill (Linda), her nephew Christopher, as well as many friends. Bonnie was preceded in death by her son Michael, her parents, and her sister.
Bonnie's enduring spirit—marked by strength, courage, compassion, and generosity—will remain with all who knew and loved her.

In lieu of flowers, the family invites memorial donations to Sarnelli House, a home for children with AIDS in Thailand founded by their friend, Fr. Mike Shea. Bonnie and Dave supported this mission for many years through fundraising bike rides and by sponsoring children. Checks can be mailed to: Friends of Sarnelli Box 88234 Milwaukee, WI 53288-0234.

Please include Bonnie's name on the check.

Plans are being finalized for a Celebration of Bonnie's Life when the sun starts to work again in the Boston area!