If I were writing this novel, I'd have done something truly unexpected and eventually make the Big-Bad turn out to be a sympathetic villain driven to horrific ends in order to protect their siblings. In this case, the "Marquess" would be a front for that old man (and whomever else is willing things—The Bigger-Bad), and thus enable the red-head to do something unsuspected like having a heel-faced-turn.
I rather want to see the "uncle" and the first or team up. I mean, the younger prince is in danger of becoming a pawn of this horror story group of traitors, which means that since the first prince only wants to protect his brother & wife, which would mean that the Marquess ultimately could have to choose between his bitterness between the first prince and the true monsters (the Emperor, who I plird already that he'd willingly "dispose" of his own child or his wife, and the Parlam family council of douchebags—tge abuser squad).
If I was going to make tensions worse, I'd make the prince realize that all of those innocent people died because of this group of monsters and make the Marquess likewise realize that he sufferes with his sister not because of the innocent first & second princes who dearly love one another, and whom would easily die to protect one another, much like he and his sister, but the Emperor and the rest of the abuser squad who catipulted them into misery.
It wasn't the first Prince's mother who caused the Empress to suffer. That was the heartless Emperor and the Parlam family elite.
I wanna see them push through their suffering to root out the real culprits, to end the mutual cycles of abuse, and see matters resolved for justice at last! <3
