Baby chickens drowning on half slabs

When baby chickens are standing on half slabs with a water (or opaque block) above them, they will suffocate like their adult counterparts. However, they do not burn like adult chickens if a lava block is above.

I assume this is a bug because the same does not hold true for baby pigs. If they are on half slabs with water above, they only suffocate after they grow up.