What if Sanji has King’s Haki? Even if it’s unlikely, this is a rare type of haki and everyone recognizes its users as powerful people and people with the potential of becoming kings and conquerors. 

The thing is, the only way to awaken it, is being in a pretty stressful situation, with overflowing emotions or trying to protect someone loved. If you think about it, of all of Judge’s sons, Sanji is the only one who could have that haki and could awaken it since his siblings can’t feel emotions so even if they had it, they’d never be able to awaken it thanks to Judge removing their emotions. Dunno if I’m explaining myself there ^^´

Now I’ll start with the madness. If Sanji awakens this during the tea party in one extreme rampage and somehow knocks out half of the guests, or even worse, half of Germa’s army, Sanji would hand Judge the biggest L ever. I cant even imagine Judge’s face if it turns out that the son he neglected has a power related to true Kings and Conquerors and the potential to possibly conquer the North Blue, it would be so satisfying.