Well when it comes to Mario and storylines it's all over the place. I mean how could Mario live to see the next Star Festival that only comes around once every hundred years and still look young? I know that Miyamoto's thoughts are usually different from the game when he doesn't work a lot on...
I love the game collection on the disc, I finally get to experience Kirby's Dreamland since the game did come out the year I was born. Also the collection book is funny, I laughed when it called Meta Knight "The coolest of the cool masked knight."
I'm going to stick with the story of them being Bowser's kids. I mean Miyamoto's canon has been different from the game cannon. His Zelda timeline is way different from the one we actually got, so we never know.