Baby Development Month-by-Month: Month 21

You will have a real character on your hands by now as your little one’s personality flourishes, and she will be keeping you on your toes daily.

Here is what you can expect at 21 months.  

Feeding and sleeping

Your child one will need around 13 hours of sleep over a 24-hour period, made up of 11-12 hours at night and an afternoon nap of 1-2 hours. It is normal to experience some problems with sleep at this age, with everything from night-time wakefulness to difficulty settling down at bedtime becoming a possibility. Try not to worry and stick to your usual routine as you navigate your way through any potential regressions, remembering that they are usually just a phase.

Where food is concerned, continue to offer your toddler three meals per day, a couple of healthy snacks, and around 400ml of whole cow’s milk or breastmilk, alongside her vitamin drops. Avoid anything high in salt or sugar and avoid adding these to her meals or offering drinks other than water or milk, which should ideally be offered in an open cup.

At this age, mealtimes can sometimes seem like a chore to toddlers as their play time becomes interrupted for food. Alongside fussiness at this age, you may notice your child stopping eating earlier than usual out of boredom rather than a full tummy. As with bedtime, it is important to try and stick to some sort of routine to encourage good mealtime habits, eating together as a family at the table where possible.


At 21 months old, your child may be saying 50 or more recognisable words and will likely be able to understand instructions and communicate her needs to you quite efficiently. She will have trouble explaining what is wrong when she is upset or tired so it can be helpful to name emotions with her when you recognise them. If she demonstrates anger for example, say something like ‘are you angry?’. Recognising the problem and saying it out loud can even be enough to side-step a simple emotion as she sees that you ‘understand’ her. 

As part of this, you may have experienced a few toddler meltdowns by now and this is completely normal, even before she turns two years old. Often the cause is frustration at an inability to do, communicate or have what she wants. Try to remain calm and work at trying to understand what is wrong from her perspective. What seems silly to an adult with a fully-developed thinking brain, may seem like the end of the world in that moment to your little one. Once you understand the root of her distress, you can diffuse the situation by showing empathy (‘I can see that you are cross’ or ‘I understand that you are upset because you cannot have that pen’) and finding a suitable solution for you both or by offering a distraction after a comforting cuddle.  

At this age, she will not yet be able to grasp the concept of sharing – this social skill will come later. Rather than insisting that she shares all of her toys during a playdate, when you notice her offering a toy to another child, be sure to offer praise and model turn-taking behaviour yourself too.

Senses and physical development

Every day will be an adventure with your little explorer as she tries to help around the house and tries to master day-to-day tasks such as handwashing and brushing her teeth. She will continue to need your assistance with these tasks for a while, but it is a great idea to encourage her independence, perhaps taking turns to get those pearly whites clean.

While your toddler may not be ready for toilet-training just yet, you might notice some signs developing over the coming months that demonstrate she is aware of when she is about to go. Look for things such as crouching down, hiding behind furniture and tell-tale footwork (standing on one leg or doing a little dance).

Playing with your twenty-one-month-old

Continue to involve your child in as many day-to-day tasks as possible – this will appeal to her independent nature, while helping to develop a huge range of skills, from communication to motor skills. You can also support her hand-to-eye coordination by placing items into boxes and letting her remove them, or playing with shape sorting toys.

Encourage her to use her imagination, turning cardboard boxes into play dens or pirate ships which she can decorate and make her own. Even the inner tube of a kitchen roll can be a telescope for her pirate ship!

As her sense of humour develops, you can play around with switching names for things she knows – call a ‘dog’ a ‘bus’ and see if she notices (and giggles). In the coming months, she may even try to mirror the behaviour with her own little ‘mistakes’.   

At this age, she will love running around and burning off some of that toddler energy so head outside and play ‘tag’, kick a ball around, or head to the park to go on the swings. Entertaining a toddler does not have to be expensive as the world is her playground.

Read together regularly, both as part of her bedtime routine and during the day when she might need some quiet time. This will help to develop her language skills, while also exposing her to a range of different concepts, from numbers to colours. Simple puzzles are also great as a quiet activity to do together on the wind down to bedtime.

Your little one will likely be familiar with a range of nursery rhymes at this age, so try leaving a word out for your child to complete, for example ‘twinkle, twinkle, little ____’, watching as she guesses correctly and with delight.  

While the above indicates what you can expect to see your toddler doing this month, it is important to keep in mind that all children are unique and will develop at their own pace. If you have any concerns about your baby’s development, talk to your doctor or health visitor.

Jen Dowding, Baby massage and baby yoga instructor, Basking Babies Laindon & Orsett

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