Ya... their son kinda messed that up by mistake since he didn't act like a normal kid...
Also I think thr phrase "ignorance is bliss" works perfect with these parents.
It's probably because in this kind of situation, most individuals are said to marry at an earlier age compared to our society hence their maturation period is quicker because they're expected to mature earlier to take on their respective responsibilities, coupled with the fact that they're older child is more mature than most and basing diana's maturity level off of cain which mentally is considered as a literal adult(〜￣△￣)〜
Their* not they're ⁄(⁄ ⁄·⁄ω⁄·⁄ ⁄)⁄
The parents, ugh.
Their children change suddenly but they just roll with it.
"I guess they grow maturely."
They 4 and 7, dammit! They're not supposed to be mature.