People talk a lot about sleep training, but sleep regression? Not so much. Many new moms are surprised to learn that a young baby who sleeps through the night won't continue to do so forever. Each developmental stage is likely to be accompanied by a change in your baby's sleep patterns.
When little ones are learning to crawl, walk, and talk, all that processing can be a lot for a little brain (and body!) to take. It's likely to keep them up at night, but you shouldn't panic. These phases start and resolve themselves (sometimes on their own, sometimes with a little help) when you least expect them to.