He will need to be if the British Monarchy is to survive. William must do what is best for the people. The best thing William could do is ensure Harry or his invisible kids are removed from the Line Of Succession. Harry also needs to lose his titles.
I dont know about what happens with underage Prince of Wales but Prince George gets the loot when William becomes King.
Had Harry not been a complete donkey he might have been the advisor to little Prince of Wales.
Yes, and his behavior has probably just added stress to the family.