Psychopaths can be innocent you know. If he is innocent it could well explain his behaviour after they died and why people suspected him.
For argument sake if he is innocent or guilty his behaviour at the funeral will be the same in either way as psychopaths have to play an act
Like the Philpotts ? Aww,now they were beside themselves ,on the tv news.

And if you believed that,you'll believe anything !! Isn't that the way you're supposed to act,floods of tears,when you've lost all your family ?
Jeremy was damned if he did and damned if he didn't.!