Actually that the one who manifest too early have problems feeling/understanding emotions and have more potential to become phychopath, and also that Chase manifested late was mentioned at the beginning of the "Kiss me if you can novel", but the manhwa adaption left it out.
Grayson is the worst case scenario, Grayson is born manifested.^^ Means he was already manifested when he came out of Koi.
He is like a "ultra"dominant alpha, more dangerous than a normal one.^^ Steward in "Kiss me liar" had one in his lab.
He suffers from Alexithymia
Poor guy . I like him because he can feel emotions but can’t understand . I would have hated him if he did bad things with malicious intents . But he just wanted to help people . I thank Dane so much for not judging him like others . I’ll always have a special place in my heart for Grayson and Dane
Grayson had is the hardest becausee he physically looks the most like Dominic, reminds Ashley of Dominic the most. Ashley has a massive trauma when it comes to his parents, if affected his view of dominant alphas, his domaniant alphas chioldren, and parenting a lot. And since Grayson is a born manifeste he releases more pheromones than a normal domaint alpha and is far more dangerous.
Steward has dangerous serial killer in his lab who claims to be a born manifested, he uses him as a testsubject.

Okay... Just got snippets of Bliss' story. I just realized the reason why most of Ashley's kids (the Millers) especially Grayson is kinda mess inside their heads is due to a fact that they differentiate into Dominant alpha from a very young age. Must be the reason why their emphathy, or emotional capabilities is lacking because it was already influence by heavy pheromones from a very young age.
That's why, if we compare, Grayson and Chase's situation, Chase has more emotion because he differentiate quiet later compare to Grayson. Meaning, he's more exposed to different emotions because differentiate was very late? It's like he's emotional capabilities are more developed compared to his other alpha siblings.
Can someone tell what age was Grayson differentiate?
Anyways, just sharing mwehehehehe