Moons 14-65 : Toddlers

Skipping over many stages of child development, this post looks at the toddler years.
See here for many more details on development.
Another good guide to development milestones is this.

The biggest change is when the child goes from an "infant" (meaning: no talk) to a toddler that talks and actively explores the environment. By one year old, a child will often use "mama" or "dada" with the right parent.

Language researchers have learned a great deal about the order in which children learn different aspects of language. Their first words are almost always nouns. Verbs come later. Early "sentences" consist of only 1 word. Then comes the 2 word stage. Etc. These stages tend to happen at particular ages.

By two years old, a child will start simple sentences of two words. By three years, the child can use sentences two- to four-words long, follow simple instructions, and often repeat words overheard in conversations. By four years of age, the child can understand most sentences.

The brain continues to grow as does the body. At birth, the brain is only one-quarter its adult size. During the first few years, the brain establishes and reinforces neuron connections as the child adapts to its surroundings. During this period of growth, individual nerves become insulated for more efficient transmission.

Parents quickly detect the emergence of the child's personality as the child interacts with the world -- tantrums, fears and favorites are quickly shown. As a toddler, the child starts to establish an independent sense of their own self.

What pieces of the child's personality are genetically determined and which stem from environmental causes is a long-discussed argument.