Do I need to introduce peanut earlier for my second baby?

Possibly, and it depends on risk tier. Babies with severe eczema or a diagnosed egg allergy fall into the highest-risk group, where the window starts around 4 to 6 months and testing beforehand is part of the guidance. Raise it at a well-child visit rather than deciding from an article.

Is the inclined sleeper I kept from my first baby still usable?

No. Inclined sleepers were banned from sale under the Safe Sleep for Babies Act, and current guidance treats an incline of more than 10 degrees as unsafe for sleep. That applies even if your baby has reflux.

Why does my second baby seem behind when my first wasn't?

The checklists changed in 2022. They now mark what 75% of children can do by an age, rather than the average, so the same behaviour reads differently against the new list than the old one. Check against the current CDC checklist rather than memory.

Second-time parents · 7 min read

What changed since your last baby: the guidance that's different now

Everything written for new parents assumes you are starting from zero. If you have done this before, you skim it, recognise most of it, and miss the part that changed — which is the only part you needed. Here is what is genuinely different if your last baby arrived three or four years ago. Not fashion, not opinion: guidance that was revised, and in one case reversed outright.

Last updated August 1, 2026

Peanut and other allergens: the advice reversed

This is the big one, and it runs the opposite way to what most parents were told. If you read an older baby book, or took advice from your own mother, you may have heard 'wait until 12 months, or 3 years, for peanut.' That was official AAP advice from 2000, and it turned out to be wrong.

The current understanding is that delaying introduction raises the risk of allergy rather than lowering it. Peanut is the one allergen with an actual age window attached, and for higher-risk babies it starts as early as 4 to 6 months — alongside other solids, not instead of them.

There are three risk tiers and they are genuinely different, which is the part most parenting content flattens. Severe eczema or an already-diagnosed egg allergy puts a baby in the highest tier, where testing before introduction is part of the guidance. That is a conversation with your pediatrician, not something to work out from a blog.

Safe sleep was rewritten in 2022

The AAP updated its safe-sleep guidance in 2022. Back, flat, every sleep — and the update is explicit that this does not change for babies with reflux, which is the exception parents most often assume exists.

Sleeping at an incline of more than 10 degrees is treated as unsafe. That rules out wedges, propping the mattress, inclined sleepers, and letting a baby finish the night in a bouncer or swing.

The federal Safe Sleep for Babies Act banned inclined sleepers and crib bumpers outright. If you have either in the loft from last time, they are not simply out of fashion — they were withdrawn from sale for a reason.

RSV immunisation did not exist for your first

There is now a genuine either/or decision to make, and it is yours. Either the maternal RSV vaccine during pregnancy, or an antibody injection for the baby after birth — most babies need one, not both.

The maternal vaccine has the narrowest window of any pregnancy vaccine: 32 weeks 0 days through 36 weeks 6 days, and seasonally restricted. Miss it and the decision moves to the antibody route, which is usually settled by the hospital team in the first day or two.

The practical thing: bring the date you were vaccinated, the actual date, to the delivery. Whether you had it, and how many days before delivery, is what determines whether your baby needs the antibody.

The milestone checklists moved in 2022

The CDC and AAP rewrote the developmental checklists in 2022 — the first substantive revision in about two decades. This matters more than it sounds, because it changed what 'not yet' means.

Milestones are now set at what 75% or more of children can do by a given age, rather than at the average. Under the old lists, roughly half of typically developing children would 'miss' a milestone by definition, which generated a great deal of unnecessary worry and some genuinely delayed referrals.

So comparing your second child to what you remember of your first is comparing against a different ruler. If something looks late to you, the current checklist is the one to check it against.

Things that quietly stopped being recommended

Wheeled baby walkers. The AAP has pushed for a ban on them for years, because they let a baby reach a stove or a staircase before judgement catches up with speed. A stationary activity centre gives the same contained entertainment without it.

If one was handed down from a friend or relative, it is worth passing straight back rather than storing.

What did not change

Most of it. Feeding on demand, contact and responsiveness, tummy time, the ordinary business of getting through a day — none of that has been revised, and your experience of it is the thing no first-time parent has.

The point is not that you need to relearn parenting. It is that four or five specific things moved, two of them in ways that affect safety, and nobody sends a notice when guidance changes.

Common questions

Do I need to introduce peanut earlier for my second baby?: Possibly, and it depends on risk tier. Babies with severe eczema or a diagnosed egg allergy fall into the highest-risk group, where the window starts around 4 to 6 months and testing beforehand is part of the guidance. Raise it at a well-child visit rather than deciding from an article.
Is the inclined sleeper I kept from my first baby still usable?: No. Inclined sleepers were banned from sale under the Safe Sleep for Babies Act, and current guidance treats an incline of more than 10 degrees as unsafe for sleep. That applies even if your baby has reflux.
Why does my second baby seem behind when my first wasn't?: The checklists changed in 2022. They now mark what 75% of children can do by an age, rather than the average, so the same behaviour reads differently against the new list than the old one. Check against the current CDC checklist rather than memory.