Ali Landes' mother had one kidney, one lung, no spleen, no diaphragm, and tumors strangling her esophagus. And yet she still fought the odds.

Wendy Landes, 56, was a renowned mediation lawyer, avid tennis player, active part of her Los Angeles community, mother of three, wife of 29 years, rock of her family—until one day when everything changed.

But the day before her mother died in 2013, Ms. Landes wondered if she should continue the walks. "I wanted to make sure that I wasn't pretending that's what she wanted," said Ms. Landes. So she asked her mother, "What do you think?” The answer Ms. Landes received was simple: Keep on.

When Wendy Landes was diagnosed with liposarcoma in 2008, her—and her family's—life turned upside down. They searched for support, but found that there wasn't much out there—liposarcoma, a cancer of the fat cells, is both incurable and rare.

[United Talent Agency] sponsors Wendy Walk, a sarcoma support group founded by [Wendy] Landes’ children in her honor. The organization has so far raised $2 million, which is “a drop in a bucket in a breast cancer world, but for us, it’s a lot,” says Landes’ daughter Ali. “When people fund an orphan cancer, their resources can go a long way.”