Baby villagers with no head....?

It's really horrible if you see when you play survival...

I found one village and there is no adult villagers but only baby villagers with no head....

I summoned some villagers with spawn egg and command in creative but I can find same ones

Also the portion of adult villagers is too small while using command block and command.

Use this in Hollowin and fix it now please.... it is too horrible to continue playing.....