I think he's jealous.

“To my son,If you are reading this letter, then I am dead.I expect to die, if no…”

“The cycle hit the beach and spun out. Emma went into a rolling crouch as she fl…”

“He took her by the shoulders and pulled her closer to him, his fingers knotting…”

“You must behave as if return is certain, not a matter of chance", Jem said.”