Book ideas?

At nineteen months old, our son C.T. is starting to become aware that he has a brother - not that he knows what it all means, but he is curious and talking about his "brodur". We have B.W.'s scrap book which we look at with C.T. quite a bit, but I'm looking for some simple book/story to think about introducing the concept of having a deceased sibling. I have looked at the common titles... "We were going to have a baby, but we had an angel instead" and "Someone came before you"..., but both are potentially confusing. The former seems to allude to babies becoming angels if they die (which we do NOT believe). The cover of the latter shows a baby-ish looking angel on the cover. Again, this doesn't align with what we actually believe or will tell C.T. Angels watching over and caring for B.W., we are okay with that..., but him transforming into an angel, that doesn't work for us.

Any ideas out there - ones you've heard of, or ones that have been helpful for you and your family?