Bienveillante

So here's the utility of the wings !

Thanks @zpp_art for the idea

The beasts can carry their babies while warming them and preventing them from falling, like swans with their chicks
But above all, it serves to protect them from their feelings when they're exposed to new emotions, sounds or things that could scare them

The parents are very invested in caring for their young, they play with them, take them on their back for a walk, and have an eye on them all the time.
If anything happens to the parent, an other beast will take care of the baby, even if they and the parent had no connection

There's no evidence that there are males and females, they're too different from the other animals to fully understand how they live...
Mystery