This Halloween, sisters Emma and Ruby Cannady, ages 8 and 5, of Abington, rocked the holiday with the absolute best costumes in the neighborhood – maybe even the region – and the other kids couldn't have been more psyched for them.

The girls have spinal muscular atrophy, a debilitating genetic disease that requires them to use motorized devices to get around.

Emma was set for a night of cruising in her own Hogwarts Express as Hermione Granger of the Harry Potter books and movies, and Ruby was ready to make Halloween history as Anna,  Frozen's feisty princess, in her own motorized sled.

To be sure, the girls had some special magic working on their side.

The Magic Wheelchair, an Oregon-based charity, and Gethrr, a do-good group based in Collegeville, joined forces to turn the sisters' power wheelchair and scooter into mechanized costume extensions – fantasy dream machines that would be cool by anybody's standards.

The Magic Wheelchair was started three Halloweens ago by Ryan and Lana Weimer, an Oregon couple who wanted to give other kids the joy their sons got from having their wheelchairs turned into fun costumes on Halloween. Three of their children, like the Cannady sisters, were born with spinal muscular atrophy. Partnering with local nonprofits around the country, the Magic Wheelchair has helped create mobile "epic costumes" for about 90 children since 2015, including nearly 50 this year.

Michael McManus, founder of Gethrr, said the chair and scooter cost about $1,500 to convert. The group's volunteers did all the work.

McManus said the girls were interviewed about their favorite books and characters. But Emma and Ruby didn't fully know what was in store until Monday evening, when they were introduced to their hot new rides. Scores of friends and neighbors, including lots of kids, came out to take part in their celebratory maiden voyage.

"We all walked all the way down the street together," said Gina Cannady, the girls' mother. "It was incredible to have the kids right beside them."

The magic of the moment for kids like Emma and Ruby can't be underestimated, she said. For children in wheelchairs, Halloween can be a time when others race ahead, a reminder to them of what their muscles can't do.

Not this year.

"I would say for the first time, honestly, they are elated to start," their mother said. "They can't wait to go out with all the kids ooing and ahhing."

Halloween may be just the start: "Emma's already talking about, 'Are we going to have a Fourth of July parade?' "