"Onze vader leest ons kinderboeken voor."

From "voorlezen" which is a separable verb and which means to read something aloud while other people listen.

Because when you read something for someone, you're reading something they should be reading (because that was their homework, for instance) and they are not doing anything at all. Also: you are reading 'to yourself', silently.

Now, when you read something to someone (or you read them something), you're reading aloud, and they are listening/paying attention.

Hope this helps.

I don't think so. I think the separable verb needs to wrap around its object.
te voorlezen = to read aloud, ik lees een boek voor = I read a book aloud or I read aloud a book.