Yeah,,and i heard it can be because of your growing up environment/ Some psychological reason / some big trauma,,
For grayson,,it's mainly because of how his father raised him,,his father never explained what he did why is it wrong,,he just bluntly punished him,,(once choked him,locked him in a basement),,so it's mainly because of his child hood environment,,
It’s not about his environment. Greyson has been indifferent even before the incident where he poisoned Koi. He’s already 8 back then. Remember how Koi went there? Nathaniel told about what the twins were doing to Chase so Koi looked for them to tell them that what they do is wrong. After telling the twins that, Greyson gave Koi the cake which almost killed him. It was out of pure anger why Ashley choked Greyson and put him in the basement. Ashley also said that after the incident he explained that it js wrong to kill someone so what Greyson did after is he instructed someone to kill another person. It’sn Greyson’s nature.

Honey!!That 'Dog' is someone's family,,and it's their duty (also yours cause you are now a firefighter) to protect everyone,,so that's why your future wife went there just to save a "dog"
---- I hope grayson read my comment and understand