Everyone acts like those kids in Undertale is the ultimate travesty, but if I found out my kid climbed up a mountain, went into a cave, and jumped/fell down a hole with a huge fall, I'd probably immediately assume they were DEAD.
If you told me "Nah they lived but then some weird underground monsters killed them after" I probably wouldn't believe you unless had actual proof. Even then, I doubt anyone gave a SHIT about those kids if they were letting them climb up that mountain.