Toddler is a term to define a child that learns to walk. Normally the term is applied to children one to three years old. The toddler years are ones of rapid change and represent a challenge most for parents. The most dramatic advances occur in language and locomotion, but progress is evident in all areas of cognitive and physical growth and development.

The average 18-month-old has a vocabulary of at least 20 words. Over the next few months, the child will experience a burst in vocabulary. At this time, a toddler can say nouns, names of special people, and a few action words and phrases. At this point, about 50% of what the child says should be intelligible to strangers. At two years of age, the child can combine words, forming simple sentences. Toddlers use language to convey their thoughts and needs (such as...