They PAID for the seat - for their 18 yr old - who then changed plans and went on a different flight - but they kept the seat they'd paid for - for their 2 yr old.
and had him in a safety seat - per Delta's STATED rules for a child.... what part of that makes THEM wrong?
Were they even offered compensation if they gave up the seat they PAID for? (I hope they have the threats - if true_ of jail and loosing their kids - ... free flying foe the rest of their days-
That is not the deal the family agreed to. If the 18yr old doesn’t use his ticket, the seat goes to someone else. This is the way it should be. More satisfied customers and more profitable. Also keep tickets prices down.