It is interesting that today is designated as Brother's Day because with my enrichment group today the word 'brother' was a topic of discussion because one of the group had read Gerald Rose's book How St Frances Tamed the Wolf and in the text St Francis called the wolf, Brother Wolf and she wanted to know why. A very fruitful discussion followed about how words could have meanings other than their literal one or common one and that they could also have 'shades of meaning'. I thought this of particular interest because the group of children were all five or six years old.
On the subject of brothers, in the more regular sense, my favourite books are Penny Dale's Big Brother, Little Brother and Margaret Mahy's The Seven Chinese Brothers. None of these three books are new, but all are well worth searching a library for.