The Allens, the McCartneys, and a handful of other families met about 20 years ago, after responding to an advertisement about play dates, McCartney said. The parents all hit it off, their young children all hit it off, and a deep friendship ensued.
When Elise got sick in 1997, the group rallied to help.
"They would show up to clean up house, or cook a hot meal, run a fund-raiser, whatever," said Elise's sister Ashley Allen, 26.
"I would take my daughter to the hospital and she'd lay in the bed with Elise, watching movies for hours," said Lelia Muckelston.
After a few years of treatment, chemotherapy, and remission, Elise passed away in 2000, just shy of her 11th birthday.
To this day, Muckelston's daughter, Julie, has a keychain with Elise's name on it; Julie had made it at camp just before Elise died. And Elise's stepmother still has a pair of the girl's earrings - which she plans to give to Julie for her forthcoming wedding.
"Her memory is able to bring everyone together," McCartney said. "Just the other day was the first time I'd seen Ashley in a couple years, but we picked up just like that."
Indeed, Sunday afternoon, they stood in McCartney's backyard, overlooking Mirror Lake, reminiscing about swimming through orange pond film, canoeing to each others' houses, and eating popsicles in the garage.
Having everyone together again, working together on the bike ride, Ashley said, is "intense. You start thinking about how little we all were."
But little Elise, her sister said, "had a bigger heart than she let on - and she was wise beyond her years."
Ashley described her sister as "a diva," a girly-girl who loved glitter and feather boas and makeup and bright colors.
Mary Allen recalled her stepdaughter as upbeat, confident, and funny. Once, at the mall, Elise spotted some old men and nudged her sister: "Know the difference between them and me? I make bald look good," Mary Allen said, tearing up with laughter.
The families gathered in the McCartneys' yard Sunday to build a a float for the Pemberton Township Annual Water Carnival and Family Fun Day.
The boat will take off Saturday and be decorated with lights and angels - an Allen family doodle that has come to symbolize Elise - and a bike will extend off the back. "The front tire will be up in the air, like it's going up to heaven," they said.
They hope the float and other marketing efforts will help the organizers meet their fund-raising goal - $1 million for the Embrace Kids Foundation, a nonprofit that supports families of children who are battling cancer or blood disorders.
As of Sunday evening, they had raised $5,700.
The "Team Elise" portion of the Dream 4 the Kids bike tour will get rolling Sunday with a 25-mile loop around Buccleuch Park in New Brunswick. Elise's father and brother, Brendan's father and uncle, Julie's brother, and several others will ride the loop before sending the long-distance riders on their way.
Brendan McCartney and four friends will spend the next month riding down the East Coast, trailed by a support van and a documentary film crew.
They'll stop along the way to volunteer at places like the Ronald McDonald House, in what McCartney calls "mutual charity."
This will be McCartney's first major bike ride. But he's been training, about 200 miles a week, to get used to sitting for so long.
And for motivation, he said: "I'll be thinking about all those other families going through what Elise's family went through."
Contact Jessica Parks at 610-313-8117, firstname.lastname@example.org or follow on Twitter @JS_Parks.
For more information about the fund-raiser, visit www.dream4tk.org.