But they've been breaking the rule. As the clock winds down on Linda's life, she's breaking it, too.
"I cry a lot these days," she says. Lying in bed, knees bent, she is frail and bony, and her hazel eyes droop with fatigue. "I always knew this was coming, but I never focused on it. I guess it's starting to hit me."
The thing is, she thought she would beat this monster. So did her parents, Bob and Sue. Her sisters, Susie and Chrissy. Her brother, Bobby. And the pals she's known forever - like Jenn Szewczak, Diane Cannon and Katie Szoste - who've organized sleepovers at the hospital so Linda would never be alone.
But the cancer had already spread when it was found during surgery to remove an ovarian cyst. Linda did chemo. Lost her hair. Got it back. Did charity walks for a disease she'd never thought about until she got it.
Then her kidneys blocked up. Fluid squeezed her lungs. Inoperable tumors invaded her bowel and stomach. She now receives nutrition through a tube.
"I dream about food," she says. "Chicken marsala, my mom's stuffed shells, any pizza from the Wildwood Boardwalk, as long as it's thin."
Last week, her devoted medical team at Cancer Treatment Centers of America in Tacony told Linda there was nothing more to be done. They wept with her when she was discharged to Vitas Hospice.
She will stay at Vitas a few days. Then she will be sent home - she is single and lives with her folks in Port Richmond - where hospice nurses will help her family care for her.
No one is sure how long she has. But it's clear the need to find funeral money has become urgent.
For 10 years, she worked as a secretary at Greenmount Cemetery in Olney, until sickness forced her onto disability. Through work, she'd had a small life-insurance policy. When the benefit was discontinued for all employees, she tried to get a policy on her own, to no avail.
"No one will give you life insurance if you're dying," she says.
So her boss gave her three cemetery plots (for her and, one day, her parents) with cement vaults. The company will pay for the opening and closing of Linda's grave. But Linda is determined to spare her family the remaining cost of her farewell.
It's killing her mom.
"She doesn't have to do this," says Sue, who is still recovering from a stroke last summer. Linda's dad, Bob, retired from his mechanic's job when Linda got sick, so he could care for her. "I tell her, 'Lin, we'll find a way to pay for your funeral.' She's always thinking about everyone but herself."
Linda's friend Jenn Szewczak tells how Linda used to take Sue to the salon every other week to get her hair and nails done. How she'd never leave a restaurant without bringing home food for her parents.
And at work, Linda was the favorite, says Greenmount's general manager, Linda Wray.
"She always had a smile and was so compassionate and kind with the families," says Wray. "We miss her so much."
As word of Linda's funeral worries has spread, those who love her are mobilizing.
Her friends have organized a men's and women's softball tournament/fundraiser on May 17-19. Called "Lace Up For Linda," it's sponsored by the Philadelphia Sport and Social Club.
At work, co-workers are chipping in to buy her a casket. And two funeral directors who've known Linda for years have offered their services, gratis.
That still leaves the death notice, the flowers, the funeral lunch and the last big bills associated with Linda's medical care.
"We figure about $9,000 will cover everything," says Jenn. "If we raise any more, we're donating it to cancer research. Linda told me, 'I need you to fight for me when I can't fight anymore.' So that's what I'm gonna do."
She starts to cry.
"I know - no tears!" she says to Linda. "But sometimes I can't help it."
"I know," says Linda softly, closing her eyes. "I know."
To "Lace Up For Linda," go to pssc.leagueapps.com/tournaments. To donate to the "Linda Belz Benefit," contact any branch of Citizens Bank.
On Twitter: @RonniePhilly