The organization was founded in 2008, part of a national "age in place" or "stay in place" movement. Hundreds of "villages" have sprouted across the city, state, and country to confront the reality that the U.S. population of adults 65 and older is forecast to rise from 37 million in 2006 to 71.5 million in 2030, according to the AARP.
Philadelphia had about 185,000 residents 65 or older in the 2010 census, 16,000 of them currently in the area covered by Penn's Village, said executive director Avalie Saperstein. The village ranges from Spring Garden Street to Washington Avenue, and from the Schuylkill to the Delaware River.
Miller is unable to drive or take public transportation, so Penn's Village volunteers often drive her to her many doctor appointments - sometimes three a day, four times a week.
She didn't want to forsake her Center City home, where she has lived for eight years, for the suburbs. Proximity to Hahnemann University Hospital on North Broad Street and Drexel University College of Medicine on Queen Lane was important.
Center City, with its hospitals, restaurants, parks and theaters, places to walk to that are hard to find in the suburbs without a car or taking a bus, exerts a strong pull. "Everything's practically at your fingertips," said board member Kristin Davidson.
All that plus the diversity of people and the hustle and bustle of the streets keeps people feeling alive, said Saperstein.
"I think it's fun," Saperstein said. "I think it's life."
Among its services, the village matches members with volunteers who assist them in their everyday lives, said Davidson.
"Even just to get on a ladder when they can no longer get on a ladder to help change a lightbulb," Davidson said.
To Miller, being a patient is a full-time job, but she didn't want it to take over her life. If she had to commute from the suburbs, she said, she would not have time to build a regular life, which is what she is working toward.
Miller works with a personal trainer who has helped her get back on her feet to make the 21/2-block journey to Rittenhouse Square.
"When I first started to walk again, that was sort of my milestone," Miller said. "It used to take me 45 minutes to walk, and I would sit there for an hour and take a cab home. Now I go there with my personal trainer and I do laps around that place."
Saperstein said volunteers don't just drive members to appointments, to the grocery store, or the doctor's waiting room - they become friends.
"Even if they're twice your age, you can really have an eye-opening, exciting conversation in the 10 minutes it takes to go from 15th and Spruce to 19th and Chestnut," Miller said.
Ellen Rapsher, a Penn's Village board member and volunteer, said a villager named "Mrs. G" needed chemotherapy treatments, but was not allowed to go alone in case of side effects. Mrs. G had no one to ask to accompany her, so she called Penn's Village.
Rapsher has been going with Mrs. G to chemotherapy for over a year and has formed a long-lasting friendship that continues outside of the hospital.
"Last time we were there was seven hours," she said. "I showed her pictures from my trip to Turkey and she said, "This is the most fun I've had at chemo ever.' "
This neighbor-to-neighbor concept gives the 200 members of Penn's Village's the company and friendship they need as well as the support.
Eileen Glass, a retired social worker and Penn's Village volunteer, created a telephone support group for caregivers in September. She said she had to take care of her mother when she developed dementia, so she can relate to the stress, emotions and feelings family members have.
Every other week, Glass holds a conference call for people to talk about caregiving issues, stress and strategies, concerns, restraints on personal life, and how to make sure their loved one is getting the best services possible. The support group serves as a way to share information and resources.
"They'll say, 'I heard about a great aide who works at this agency and it's not that expensive,' " she said. "Or someone will say, 'Well, you should call this agency,' or, 'Here's a number of this friend.' "
Penn's Village board member Pat Harner runs additional information sessions and workshops for members, such as a medical series that advises people on how to talk to their doctor, how to create end-of-life documents, and update medical records.
Other workshops focus on how to use the latest technology, how to communicate with "young people," and how to de-clutter a home.
Davidson said some people call it "the best-kept secret of Center City." For Miller, though, it's the people.
"This neighborhood is sort of like my Cheers," she said. "You may not have best friends on every corner, but I can't walk around the block without seeing a familiar face."
Contact Karie Simmons at KSimmons@philly.com or @ksPhillyInq on Twitter.