Pearl is over the moon when she gets the fin-tastic news that she's been picked to be the next Winter Princess! She can't help gushing to Shelly, Kiki, and Echo about the beautiful dress she'll get to wear and how all eyes will be on her when she makes her big speech at the Winter Festival. She can't wait to tell her parents!

But her parents have some news of their own...Pearl is going to be a big sister! They're adopting a baby boy, and he'll be coming home with them right around the time of the Winter Festival. Suddenly, instead of glittering gowns and princess tiaras, Pearl has to talk about new cradles and baby toys. How can her new brother be stealing all of her parents' attention before he's even here?

Can Pearl convince her parents that a messy, noisy baby is the last thing they need? Or will she discover she's more suited to being a big sister than she thought?