Can you present anything that would reasonably convince me that this is true?
Depending on their age and maturity and the situation at hand. But I also do everything in my power so that they don't suffer.
I know Ecclesiastes, and I know the author was clear that there are no rewards waiting for anyone beyond this life:
3 This is the evil in everything that happens under the sun: The same destiny overtakes all. The hearts of people, moreover, are full of evil and there is madness in their hearts while they live, and afterward they join the dead. 4 Anyone who is among the living has hope - even a live dog is better off than a dead lion!
5 For the living know that they will die,
but the dead know nothing;
they have no further reward,
and even their name is forgotten.
6 Their love, their hate
and their jealousy have long since vanished;
never again will they have a part
in anything that happens under the sun.
Ecclesiastes 9:3-6
The author of Ecclesiastes says that there's no real explanation as to why some people have good lives and others have awful ones and that we should try to enjoy this life while we have it. It's a good message. I'd also like to point out that it runs in contrast to explanations found elsewhere in the Bible, where it's made plain that god makes people suffer for their sinfulness.