What on Earth happens to babies around 15 months?
Has your predictable walking baby dramatically changed almost overnight? Are they constantly seeking the breast, needing to be picked up but not wanting to be carried and not sleeping as easily?
Welcome to the shift which happens around three months after the first birthday!
While we celebrate twelve months of life outside the womb, 15 months is when infants really evolve into toddler hood. Most have progressed from taking steps to walking the majority of the time. They are beginning to explore words beyond the initial M(um), D(ad), B(ub) sounds we identify as language (even though these are universal across cultures, who mostly use similar words for these meanings).
It is around 15 months that we see some of the more frustrating signs of development:
Big Feelings begin to be expressed in what have been described as temper tantrums. What we are really seeing is the unfiltered reactions we all experience every day when we are disappointed, frustrated, annoyed, overwhelmed etc. Without the brain development needed to regulate emotions, toddlers react as if it is the end of the world simply because, to their immature brain, it is. It takes a human brain 25 years to fully mature.
Selective Eating appears around this age. The transition to family foods occurs between 6-12 months, when baby brains are hard-wired to taste everything. A growing suspicion of unfamiliar foods in the second year is possibly a protective factor - perhaps to minimise toddlers eating unsafe plants in our hunter-gatherer past. Coupled with multiple erupting teeth which can make chewing uncomfortable, it is not surprising that beige carbohydrates, dairy like cheese and yoghurt, and sweet fruits replace vegetables, meat and other chewy textures for many toddlers.
Interrupted sleep increases. Despite the mythology around babies sleeping through the night, the second year of life often sees an increase in night waking, alongside difficulty settling to sleep without the breast day and night. Rapid brain development often brings wakefulness and motor development often brings movement in sleep. As the body moves about during light sleep, the child wakes and needs support to resume sleep. Bed-sharing parents will notice the infant seeking the breast more frequently during the night while those who sleep away from their child will be wakened frequently to settle their toddler.
Increased breastfeeding. Independence is blossoming as the walking baby discovers the ability to initiate activities: including breastfeeds. This can appear as demanding the breast multiple times when mother and child are together, even though they go long periods between feeds when apart. This can feel overwhelming but is generally a short-term stage which passes.
Researchers from Oxford University Baby Lab and Bristol University Baby Lab used fNIRS to study brain activity in 16-month-old toddlers. They tested 103 toddlers on a touchscreen task that measured inhibitory control skills. Results showed changes in brain regions used for this skill compared to when they were 10 months old.
Brain changes happen in toddlers aged 10 to 16 months, even if their skills stay the same. A study showed that as babies become toddlers, they still have trouble stopping habitual actions, but the brain areas involved change significantly. This suggests that at 16 months, toddlers use more brain regions compared to 10 months, even if their abilities seem unchanged. The findings highlight that 16 months is crucial for brain growth, helping toddlers follow instructions and manage impulses.
Abigail Fiske and Karla Holmboe led a study showing significant brain changes from infancy to toddlerhood, with no improvement in inhibitory control skills. This research provides insight into brain development and the progression of inhibitory control from infancy to adulthood.
Drs. Fiske and Holmboe found that toddlers have difficulty controlling their actions as their brains change to help them learn new skills.
Although this stage does pass quickly, it is followed by a similar but less intense unsettled period around 17 months. But by 21 months, things are beginning to stabilise and you might have a settled few months.
Further reading:
Why Toddlers Wake In The Night
Toddlers Don’t Sleep Through the Night Either!
Night Weaning a toddler: can it be part of your gentle parenting journey?
Why Do Breastfed Babies and Toddlers Play With Their Mother’s Body?
