Most twins, triplets and more grow and develop along roughly the same lines as their singleton peers – even those who start out much smaller will catch up in time. But there's nothing to say twins, triplets or more have to reach milestones at the same time as each other. The exception is for identical twins or triplets, where you can expect the babies to have a pretty similar pattern of growth and development.

Try not to compare your babies with others – multiples sometimes take longer to reach milestones, especially if they were premature. Health professionals will make allowances for this when they monitor development. A singleton pregnancy usually lasts forty weeks, so if, for example, your babies were born at thirty-five weeks, their progress will be monitored as if they are five weeks younger than they are.

If you have a child or children with additional support needs, we have an online community support group on Facebook for parents and carers of twins, triplets or more that you might like to join. 

*These milestones are a guide only, if you have any concerns or questions regarding your babies development or reaching milestones you may want to contact your health visitor or GP for advice.

  • Around 3 months you can expect your babies to be responding to you by smiling, lifting their heads and maybe using their forearms for support.
  • Between 3 to 6 months babies start to be able to tell a stranger's face from a more familiar one and will show signs such as excitement when they see preparation for their feeds by smiling.
  • Between 6 to 12 months your babies will be starting to make sounds such as babbling, cooing, and laughing and will enjoy games that interact with their carers such as peekaboo.
  • Between  9- 12 months your babies may be able to sit unaided for a short time and might be starting to attempt crawling or the first stages of moving.

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 at their own rate, 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.


Multiples can be slower than singletons to develop language. However, many multiples show no signs of language delay.

Potty Training

Potty training two or more isn't usually as difficult as parents expect it to be and in most cases soon becomes a distant memory.

Creating routines for your twins, triplets and more

Many parents find having a routine is invaluable in caring for more than one baby. A routine needs to be flexible and something that works for you and your family situation.


Twins Trust have resources and videos to guide you through play with your twins, triplets and more right from birth and as they develop.

Twin Studies

Twin studies are used to investigate the roles of genetics and environment in various traits, behaviours and conditions.