University of Maine cooperative extension offers a nice pamphlet series called The Growing Years. There’s one per month, from 0 – 12 months, every other month from 12 – 24, and every 3 months for 3 and 4 year olds.
They talk about how baby is changing, what developmental milestones are coming up, temperament and gender issues, how you can help your child learn, and issues such as screen time, poisoning prevention and more. Find them all here.
Note, although there are prices given for how much it costs to buy a physical copy, you can download them for free! See the links where it says “Download it for free: PDF (for printing) / HTML (for browsing)“