Addressing Treatment Nonresponders

The goal of this clinical trial is to see if providing late talking toddlers who are not responding to the Vocabulary Acquisition and Usage for Late Talkers (VAULT) treatment with a different way of communicating will help them improve their word learning. Participants will start with VAULT word learning treatment. If, in the first few sessions, it looks like they won't respond well, they will be provided with a Big Mack Augmentative and Alternative Communication device (a button that says a word when you press it) to use for their responses. The investigators will see if this modification will help with word learning.