Baby's First Year
Month 12 — Happy First Birthday!
Baby This Month
approximately 75–80cm and 9.5–11.5kg (birth weight approximately tripled)
Your baby has completed their first trip around the sun — and the transformation from that tiny, helpless newborn to this opinionated, curious, mobile little person is staggering. Most one-year-olds are pulling to stand and cruising, with many taking their first solo steps. They have one to a few words used intentionally, understand simple instructions, wave, clap, point, and show clear preferences and personality. They know who their people are, what they like and don't like, and how to let you know. Their birth weight has typically tripled, and they've grown about 25cm since they were born.
The 12-month well-child visit is one of the most comprehensive of the year — developmental screening, hearing check, growth measurements, and vaccinations including MMR, varicella, and hepatitis A in many schedules. After the first birthday, whole cow's milk (full fat) replaces formula, and breastfeeding can continue alongside solid foods for as long as you and your baby choose. Toddler milks are not necessary and not recommended by most paediatricians — whole cow's milk and a varied diet are all your baby needs.
In just 12 months, your baby's brain has grown from 25% of its adult size to about 75% of adult size — adding roughly 50% of their eventual brain volume in a single year. No other organ grows at this rate. No other period of human life comes close to the neural density of the first year. The experiences your baby had this year — every face you made, every song you sang, every cuddle and conversation — are permanently woven into the architecture of their brain. You built a person. That's extraordinary.
The first birthday party is for you, not your baby — they have no idea what's happening and will probably cry when everyone sings. Keep it small if you can, schedule it around their nap so they're not overtired, and lower your expectations for how it will go. Take photos, eat cake, and know that the real celebration happened 12 months ago, and every single day since. You did it.
From 12 months: switch to full-fat cow's milk (max 400ml per day to leave room for food), continue a varied diet, and stop formula entirely. No low-fat milk until age 2 — the fat is essential for brain development.
This content is for informational purposes only and is not medical advice. Read full disclaimer
Take a moment on the first birthday to acknowledge what you both went through this year — the sleep deprivation, the learning curve, the hard days. It's genuinely one of the most demanding years of any parent's life. Celebrate each other, not just the baby.
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