Mario and everyone seem to forget how events turned out in the past, who they encountered, who has helped them, betrayed them, or anything. It wouldn't hurt to give a little shout-out to times gone past. It's like they're all dogs and can only really live in the present with no idea of the future or past.
"I know Bowser is behind this! Will he ever tire of tormenting us?" ~Peach, Super Mario 64
"What?! Bowser's kidnapped Princess Peach? Again?" ~Goompapa, Paper Mario
"A strange old man in a white coat gave it to me..." ~Bowser Jr., Super Mario Sunshine
"Wait...Princess Peach? The one who gets kidnapped by Bowser, the Koopa King? The one you rescue?" ~Goombella, The Thousand-Year Door
"I tried to kidnap you a while ago, didn't I? Yeah, that didn't turn out so well, did it?" ~Kamek, Partners in Time
"I think I'll move my research to Boo Woods." ~Prof. E Gadd, Partners in Time
I mostly pulled these from memory, so they aren't the exact words, but you get the picture. There's hope. :P