His parent's actions seem very vengeful and an overreaction for what he did.

He's a vengeful character when things don't go his way as fans remember when he pays Boba Fett to deliver Han Solo to him for losing a cargo of spice to an Imperial patrol.

You must accept them for exactly what they are, and not attribute human failings to them such as being stubborn, vengeful or having selective hearing.

Basically, Poison Ivy and Mr. Freeze are out to destroy Gotham for their various and vengeful reasons.

A Scorpio male can be very vengeful if he's betrayed by his lover or discovers your feelings for him weren't real or as deep as his feelings for you.