I didn't see any special from the 3 years or 4 years of his son. But I do see some strange on how the parents behaves potentially influencing the kids.
I strongly recommended that the parents visit the Dr’s immediately.
I think the parents of this boy needs to see a doctor to see if they are ok mentally. Believing in something is one thing, coming to be addicited to it is another thing. The latter is surely in a state of mental sickness.