The Mystery of the Missing Cubchoo!

While training for the World Tournament in Undella Town, Ash & co. bump into a trainer who is looking for his Cubchoo which disappeared from a locked room in the house. While investigating, Cilan comes to the conclusion that Cubchoo has been kidnapped. However, as they go further into the forest, they soon find a Beartic and assume that Cubchoo has evolved. Has Cubchoo evolved and was it really kidnapped?