Set oven to 325°F and grease a 9-inch pie dish.
Combine graham crumbs, butter, and sugar; press into dish; bake 8–10 minutes; cool.
Beat cream cheese and sugar; add eggs one at a time; blend in vanilla and sour cream.
Divide filling into 4 bowls; tint with pink, blue, yellow, and green gel colors.
Spoon colored fillings onto crust and drag a toothpick through for a soft marbled pattern.
Bake 35–40 minutes until center holds a light wobble.
Keep pie in turned-off oven with door open for 15 minutes.
Refrigerate at least 4 hours or overnight before slicing.
