When Mary Kate Mellow’s three-year-old daughter fell in love with ballet after seeing Cinderella with her grandparents, the Montclair mother of two searched in vain for a ballet DVD geared to young children. She discovered that her friend and neighbor, Stephanie Troeller, 42, a mother of four who had grown up dancing, was similarly frustrated. “It was a shame there was nothing our girls could get up and dance to,” says Mellow. The two set out to create a DVD. They dressed their daughters and other girls in leotards and tutus and hired professionals to tape a dance party in Troeller’s backyard. “We started with the joy of the children and went from there,” says Troeller.They purchased the rights to the Paris Opera Ballet’s Swan Lake, then combined those scenes with footage of young students from the School of American Ballet at Lincoln Center demonstrating basic steps. They added a montage of toys and live animals performing the moves. Troeller—a former cartoonist who worked at Hanna-Barbera, DC Comics, and Warner Bros.—designed a cartoon fairy named Prima Princessa to narrate the DVD. After a year of work and a $50,000 investment of their own money, Mellow, 40, who used to run a wholesale jewelry business, and Troeller had their first installment of Prima Princessa, a fun and colorful 40-minute DVD for budding ballerinas. The formal Swan Lake scenes are enchanting, but the intended preschool audience is assured that bouncing around the living room is fine, too. “We just wanted to share the joy of dance with our children,” says Troeller.The $19.99 DVD launched in late November. Prima Princessa Presents Swan Lake has been picked up by Amazon.com and is currently ranked third in sales for children’s dance DVDs. It’s available nationally in Capezio Dancewear stores and other shops, five Learning Express stores in New Jersey, and at primaprincessa.com. So far, the duo has distributed about a quarter of their stock without advertising. If Prima Princessa continues to sell, they plan to create installments featuring other ballets and, eventually, dances from around the world. But they’re not in a rush. “This really is a mommy venture,” says Mellow.