Samus: Killed by Ridley and has a mommy issue with a Metroid.
Lucina: Killed in her timeline
Bowser Jr: Is Shigeru Miyamoto
Shulk: Died before his eyes freezing to death
Pokemon Trainer: Sends him on a perilous journey
Bayonetta: Killed by a kid wanting to take over the universe

Jesus, Bayonetta, you gotta be more sensitive about these subjects!

Bayo REALLY needs to chill with that taunt.

btw you forgot:
Bowser: Orphan. he was raised by Kamek (see Mario & Luigi Partners in Time)
Rosalina: Mom also died and is burried under tree.
Cloud: Killed by Sephiroth
Corrin: Killed right in front of his eyes moments after their first meeting.
Ike: Killed by his father when he went berserk
Ryu: both parents died when he was a baby
Mewtwo: Created by a bunch of scientists that he killed himself minutes after being born.
Marth: Murdered while Marth had to flee his kingdom
Sonic: was separated from him (Sonic Underground)/ was transformed into a mindless robot then later rebooted out of existence (Archie comics)