Final answer:
In contrast to full-term babies, premature babies usually take longer to reach developmental milestones. Infancy is a period of rapid growth and change, and there are key milestones such as sitting, holding up the head, and cognitive development that are expected at certain ages.
Step-by-step explanation:
Understanding Infant Development
Premature babies typically take a little longer to hit major developmental milestones in comparison to full-term babies. These milestones are age-related markers in a child's life where they achieve new skills and abilities. Infancy is a critical period of growth, and during this time, infants go through numerous changes in size. For example, by the end of the first year, babies typically double in length and triple in weight from when they were born.
Key Developmental Milestones in Early Childhood
In early childhood, including the toddler stage (12-24 months old), there are several developmental milestones that are looked for to gauge a child's progress. Some of these milestones include the ability to sit unassisted, usually by around 7 months of age, holding up the head, which most babies can do at 6 weeks old, and cognitive milestones like responding to verbal requests and understanding object permanence. Toddlers generally experience significant physical growth, although at a slower rate than during their first year.