Rhine, Rhine, Go Away

There's nothing like a relaxing vacation, and that's just what Piper is having - nothing like a relaxing vacation. When work delays Mark, a heavily pregnant Piper takes Megan and Cassidy to the beach with Sarah along to "help," but Piper is all at sea when her daughters turn into mermaids, leaving her with little time to figure out how to switch them back before her husband arrives on the weekend. Drowning in troubles caused by a greedy carnival owner, a missing mer-prince, and a crafty Sea Witch, Piper soon finds herself in over her head!