Since he can't function on his own thinking, he was taught the method of copying sentences from movies, people he know etc. He observes evrything and store whatever he heard im his mind so that he can use thise words later in a similar situation. Steward, the Dr., fed the dog thing in his mind. He researching on Dom Alphas always used to say that Alphas can do it with dogs it(i think he actually want to research on that part ). He said that in Kiss me Liar too, if anyone remember. And Grayson can't differentiate between what is wrong and what is right. He can't understand if it's is a joke or serious statement. He just take the statement as it has been told.
I can forgive a brother who unintentionally traumatized his brother while trying to help him
But I can't hate a brother who happily volunteered to be a lab rat for his brother.
Many of his actions were wrong amd harmful but there was never a single percent of malice in his heart.

Wait what?? Is this chase miller's annoying brother? I knew the name sounds familiar