Snowball now has the coloring common to his breeding as a flame point-Siamese mix, according to shelter adoption manager Kerri Taylor, but the cat was snow white when he was born.
Raven's mother, Laura Hartley, of Corvallis, Ore., said Snowball was one of a litter born to the pet cat of the Hartley children's nanny's mother.
Raven doesn't know Snowball is coming home and will be "over the moon" when he steps out of his cat carrier at the airport, Hartley said.
Raven and Snowball were "made for each other," Hartley said.
"He goes where she goes. He follows her like a dog."
The Hartleys are still missing Snowball's sidekick, Shaggy, with whom Snowball disappeared last August while the family was in the midst of moving from New York state to Oregon.
Kerri Taylor said all cats and dogs coming into the shelter, on Lombard Street near 13th, are scanned for microchips.
Thankfully, Hartley had updated Snowball's contact information with one of the microchip tracking companies, Home Again.
Snowball was brought in and scanned on March 31.
Taylor contacted Home Again, which put her in touch, that day, with Laura Hartley.
Snowball has to fly in his carrier as "animal cargo" and the Hartleys weren't able to find the right flight for Snowball until Friday.
He is being taken in his carrier to Philadelphia International Airport by shelter assistant manager Leslye Lambert.
They'll miss Snowball at the shelter.
"He's sweet as pumpkin pie," Taylor said.
But amid all the sad stories of animal abuse and abandonment, "once in awhile you get these miracle-type stories where people are reunited and it really makes our jobs worth it," she said.