I’ve been trying to come up with siblings for my next gen line up and came up with Enthalpy while stuck in rush hour traffic with my friends while it stormed and we were trying to get Ich medicine for my fish tank.  
Just imagine Discord holding baby Enna and mourning the loss of his perfect name. How her name should have been Enthalpy instead. And then he runs off to Fluttershy insisting they need a new baby because he has the perfect sibling name.  
Enthalpy is a bit younger than Enna and a lot smoler. Hes the mischievous one that embodies his fathers chaos.  
It pisses a lot of people off.  
Including Enna.  
Especially Enna.