Children move through the stages of childhood at different rates. How far and how fast they master new skills is what we mean by development, but it’s important to remember that this is not a race. All children develop according to their individual strengths, and they don’t have to do it at the same time as anyone else – including a fellow twin or triplet.
Your children may seem smaller than their singleton friends. Twins are usually smaller at birth than singletons, and triplets are smaller still. Initially a child born prematurely is less likely to reach milestones at the same age as a child who was born at full term, but over time this decreases.
Your children may reach developmental milestones at different rates to each other .This is not usually a problem as long as it is handled sensitively. The best advice is not to compare your children with each other, or with other children. Allow them to be individuals (particularly with identical siblings), and accept and value their differences right from the start.