Difference between Ward and Adopted

A ward and a guardian...

Richard 'Dick' Grayson

Dick is a ward and Bruce is the guardian

Contract shows that Bruce is his guardian till he adopts Dick or till Dick is 18 to move out. When he is 18 he has to move out or will be shown as a gold digger.

Bruce might have raised him as a son and acknowledges as his son but legally he's not. Dick at age 23 can't be adopted.

Jason Todd Wayne
Tim Drake Wayne
Damian Al Ghul Wayne

Are legally Bruce's sons, adopted or blood related.

What happens if the 3 sons of Wayne didn't know this fact till at the Gala?

Also I don't own DC. Just the plot basically. Mostly. Since I got it the idea by a book mentioning that Dick was a ward and not adopted and couldn't get any of the assets described in Bruce's will when he was "dead" by a loophole. While the other batfam got their assets and Dick's.