Looking for some book recommendations...

For the bio kids in a family that’s fostering? Our bio and foster kiddo are 9 days apart and have been together since 6 months. They are almost 2 now and it’s still looking like we’re moving towards reunification which is going to completely devastate everyone but particularly both the kiddos. We’ve found some great stories geared toward the kiddo in the system but not for the bio kiddos losing a foster sibling.