there's something very distressing about that fact
From the TV Tropes Wiki:

Monster Rancher, an anime on Fox Kids TV, ended its second season with most of the cast sacrificing itself in a fight against the Big Bad. The main hero was sent back to Earth in shock. There was a third season where they were resurrected, but it was not shown on network TV.

. . . I think it says a lot about me that MONSTER RANCHER is the kids' anime series I remember with the most critical fondness from my childhood. (The one that influenced me the most was SAILOR MOON, and the one I love but wince at more often than not is probably DIGIMON.)

Because, well. The third and fourth seasons were never translated, the two seasons in which all the happy endings occur, and as far as I knew (since, uh, MR anime has never had much of a fanbase, or a resource site) that second season finale was the end.

MONSTER RANCHER? Aired on the Fox/BKN kids TV two-hour block on weekday mornings. You know, the stuff you'd watch before school started? Yeah.

It's a kids' show where everybody dies at the end. And they aired it on TV before school.

My perception of what "for the children" means was forever warped, thanks to that.