Your baby: 4 months old

Rolling over and grasping

Some babies are learning to roll from their tummy to their back at this point, which means tummy time is rapidly coming to an end. Another big accomplishment comes as your baby learns to bring objects to their mouth to taste—a good-news/bad-news development that will add a lot of slobber to your life. It’s great for your baby’s ability to self-soothe and gnaw on everything to ease teething pain but harder for you with the extra care you need to keep small objects away from grasping fingers. A good rule of thumb is that anything that can fit through a toilet paper tube is a choking hazard and should be kept away from your baby.

While advice about when to start solids is still evolving, some babies may be ready to try a few new foods now and it can be exciting to start experimenting. Babies who can sit up on their own and control their head and neck are showing signs of readiness. If they lust after your food so much you feel guilty, they may be ready for a taste. Learning to bite, chew and swallow—all tongue, no teeth—doesn’t always come easily, so the first spoonful may be met with a tongue thrust that pushes it right back out again. Don’t force it—there’s still plenty of time. (In fact, many people recommend waiting till six months.) Babies also have a strong gag reflex, which can be scary at first but a good defence against choking. This is also a great time to invest in a baby CPR class—there’s no better knowledge to never have to use.

What foods to start with? Fruit and vegetable purées are a common first choice, as well as iron-fortified cereals, but don’t limit yourself if your baby wants more. Babies shouldn’t have honey until they’re at least a year old due to the risk of botulism, and avoid choking hazards like whole grapes, nuts, raisins and popcorn. If baby isn’t eager to eat and every spoonful ends up on their chin and down their bib, wait a week or two before trying again.

Contrary to previous thinking, paediatricians are convinced that starting some of the most troublesome foods earlier rather than later may reduce the risk of developing food allergies, especially peanut allergies. Early exposure is believed to reduce the risk of allergies, which means baby’s first foods should include nuts and eggs, along with more traditional first foods, like pears and sweet potatoes. How to start? Try watered-down nut butter spread thinly on toast—they can suck or gnaw on it. Just keep in mind that too much can be a choking hazard, and whole nuts are a no-no. Easy-to-gum, nut-flavoured puffs are another option. Families with a history of allergies and other signs of high risk may want to consult with baby’s doctor about first attempts, which can sometimes take place in a doctor’s office. It still makes sense to wait at least two days between each new food so that you can pinpoint a problem if baby has a reaction.

The world of events marks another mental leap sometime in the fourth month, around week 19. Your baby is figuring out that their lives are filled with familiar events and making the developmental connection that the start of a familiar event will lead to the same ending every time. The ability to predict what is going to happen next is a great gift for your baby and a signal for you to start locking in those routine moves that let them know it’s time to eat, sleep, cuddle or go in the car.

The well-baby check-up at four months is a good time to ask all those questions you’ve been saving up about sleep troubles and starting solids, so bring a list of concerns in case you forget. The visit will also bring your baby’s second set of shots, which hopefully aren’t as stressful (for you—your baby isn’t worried about them!) this time around. Your baby’s healthcare provider will ask about your infant’s budding skills and do all the routine height and weight measurements to ensure that they are growing. The American Academy of Pediatrics (AAP) recommends that moms be screened for postpartum depression at the four-month check-up as well, so ask if you have any questions about your moods or those of your partner.

All those developmental milestones and mental leaps can bring madness back to your midnights. The baby who was sleeping long stretches is suddenly waking up to scream, startled by noises they used to sleep through, probably in the full throes of teething. It’s enough to make you cry intermittently through the night, amirite? The four-month sleep regression is a real thing: Your baby’s brain is beginning to mature and cycle through various sleep stages, light and deep, and takes the tricks learned through the day and practises them at night. How to survive? Shake it up a bit. Be open to new tricks (like white noise machines and multiple pacifiers planted around the crib), and be flexible enough to recognize old tricks that no longer work (rocking may stimulate when used to soothe).

According to some experts, four months is when baby is ready for the first steps of sleep training—a topic designed to spark debate and sow division among families and friends alike. But this, like so many decisions of early parenthood, may come down to your level of exhaustion and your baby’s temperament. The first step is to get your baby on a regular routine and sleep schedule, which starts with solidifying the morning nap, eliminating catnaps and resigning yourself to arranging your day around baby’s need to sleep.

Baby brain or baby boost

Forget your keys everywhere? Can’t remember why you entered the room? The foggy forgetfulness of the much-maligned “baby brain” has a bad reputation, but there are proven positive effects of new motherhood as well, including feeling less stress.

There’s nothing like a new baby to shine a light on every weakness in your relationship—and find new ones. Keeping your partnership strong takes work, which is the last thing you want to do (or second-last thing, after sex?) when you’re sleep deprived and covered in spit-up. Here are a few suggestions for rebuilding connections, resolving parenting disagreements and, yes, working sex back into your life (if not your night).

Getting baby to nap in a crib

Baby’s mental leaps may mean the end of your wandering ways, when baby slept on the go. Transitioning baby to a crib may take practice, along with some clever tricks, like “bum first” and mini bedtime routines.

When it comes to travel, a road trip is one of the easiest first trips for baby, but it can be hell on wheels as well. It’s easy because you’re not limited to just one suitcase, and you can stop and stretch your legs (or stop the screaming) as needed. But car trips come with challenges as well. Because road safety requires baby to be restrained for hours, it’s impossible to nurse while baby is strapped in (is there any way to do this safely?) and options for keeping baby entertained are limited. Preparation is half the battle.

Does your baby need a website?

Baby is likely a star on your social media by now, but do they have their own Instagram and Facebook accounts? Have you reserved their email address? Some parents think it’s the smart thing to do.

Read more: Your baby: 5 months old Yes! Sometimes it's OK to wake a baby from a nap