Mobs made of Minecraft's most basal blocks

This is mob is called a Block Baby and it's a cute companion mob that follows you around, can't be hurt, and phases through blocks. Perfect for players who just want some company without worrying about it dying and who don't really care about extra benefits. It will always keep up with your pace and it floats above the ground, so if you were to fly with an elytra, it could easily follow. The body is shaped like a block with eyes. The body's texutre is the same as the block that it's made of. Some examples of blocks that it can be made of are dirt, stone, netherrack, endstone, etc. It has eyes that have differing expressions depending on your activities. When you fight it will be angry, when you heal it will be happy, when you get hurt it will be sad and when you're not doing any of those things it will have a neutral expression. You can turn a block into a block baby by right clicking it with a special item made of a bottle of enchanting, soul sand, gold and any seed. When you turn a block into a block baby you're left with only half a heart, as if it takes some of the player's essence to make it alive. Right clicking a living block baby with this same item puts it to sleep, but can also wake it back up.

A way to teach players how to use it could be to give it a glowing enchantment effect when near the blocks that can be made into block babies