It's singular vs plural - You are one person, your stuff is "Chris's Stuff" (with the extra "s"). If you and another Chris pool your belongings, that stuff woul

It's singular vs plural - You are one person, your stuff is "Chris's Stuff" (with the extra "s"). If you and another Chris pool your belongings, that stuff would be "the Chris' stuff" (without the extra "s", pronounced identically).