Doll People #3: The Runaway Dolls by Ann Martin
Best friends Annabelle Doll and Tiffany Funcraft have stumbled upon an unexpected visitor, a new doll named Tilly May. She's arrived in a mysterious package...but she looks so familiar. Could she be Annabelle's long-lost baby sister? It'll take a runaway adventure to find out for sure. Are the dolls ready for life on the road?