What would be evil is if DH died and left everything to me and then I left 100% to our 2 DC and cut DSS out.
Hopefully what I am about to write will make sense...
The onus must be on each parent to ensure all of their children are treated equally and fairly.
Imagine each parent has 100% of assets to be split between their children equally. In my scenario, DSS is his mother's only child.
So, DSS will get 100% of his mother's estate and 33% of DH's.
Our DC will get 50% each of my estate and 33% each of DH's.
So...
DSS will inherit 133% of his parents' estate
DC1 will inherit 83% of her parents' estate
DC2 will inherit 83% too.
I just cannot understand how that would be unfair?