The young boy noticed that Therius communicated something telepathically to Emma's three friends and that was why they suggested they take Alderaan away and spend time with him.
It made him doubt their intentions.
But more than that, Alderaan never thought he'd be able to do something like this. He never realized he could pay close attention enough to notice what others were thinking and only chose to not say anything.
Alderaan's uncle, the brother of his mother… used him as a way to earn money.
Even though Alderaan's body slightly shook at the thought of his uncle who found himself taken care of Therius or his men for the mistreatment of Alderaan, useful thoughts still lingered in the back of his mind.
According to his uncle, Alderaan was extremely lucky to have taken after his mother in terms of mage powers. Even he knew that it was rare for a mage to take after their parents.