I love the concept behind this book: rejection of a new sibling is only permitted by the old sibling and is to be considered outright rude from outside party members. Lilly's parents pour on the love when baby Julius is born, but Lilly is hard to adjust. In fact, she tries everything imaginable to get rid of (or at least antagonize) Julius. Her veracity and commitment matches that of her parent's in their attempts to continue to show love to Lilly. But when a cousin insults Julius using the same harsh criticisms Lilly once used, big sister finally draws the line.
It makes me wish I had an older sibling.
...and it makes me hope I was (am) a good big brother.