Paediatricians recommend it from birth
In its 2024 policy statement on literacy, the American Academy of Pediatrics recommends that paediatricians encourage shared reading beginning at birth and continuing at least through kindergarten.
The statement ties shared reading to children's language, cognitive and social-emotional development, and to the relationships built around it. The part that is easy to miss is the last one: a book read together is time spent together.
The early years are when the brain builds most
Harvard's Center on the Developing Child describes the early years as the most active period for establishing neural connections — while stressing that new connections can form throughout life.
In the Center's words, early experiences and exposures, including responsive relationships with caregivers, shape the architecture of the brain and provide a strong or weak foundation for later learning, behaviour, health and well-being. Reading aloud is one of the most ordinary forms that responsiveness takes: a child points, a parent answers, and the story waits while they do.
What brain scans have found — and their limits
A 2015 study in Pediatrics scanned 19 children aged three to five while they listened to stories. Children with more reading at home showed more activation in a left-sided brain region that supports understanding language — the area involved in extracting meaning and picturing what a story describes.
That study was small and cross-sectional, and its authors are clear that it cannot establish causation: it shows that more home reading went together with that pattern of activity, not that reading produced it. It is an encouraging finding, not proof.
The words add up
Researchers at The Ohio State University estimated how many words children hear from picture books by counting the words in commonly read titles. By their estimate, a child read one book a day hears about 290,000 more words by age five than a child who is never read to — and a child read five books a day hears about 1.4 million more by kindergarten.
Those are estimates of words heard, not of words learned. But book language is different from everyday talk — richer vocabulary, longer sentences, things that are not in the room — and much of it a child meets nowhere else.
What tends to help
These are our own practical suggestions rather than research findings. Little and often is easier to keep up than a long session, and a routine that survives a busy week does more than an ambitious one that does not.
Let a young child interrupt. The questions, the pointing and the reading of the same page twice are the reading. And a book a child recognizes — their own house, their own dog, their own name — is often one they ask for again.
Where a book like ours fits
Penwynn makes picture books written and illustrated for one particular child and the people around them. We do not claim a personalized book develops a child's brain better than any other good book: the evidence above is about reading together, and any book read together counts.
What a book about them can do is make the habit easier to start. A child who is the hero of the story tends to want it read, and the adult reading it has seen every word and every picture before it was printed.