My script seems to duplicate it's parent's parent. Why?

local iCopy = game.ServerStorage.DFDIllness:Clone()
iCopy.Parent = torso
iCopy.Parent = rightleg
iCopy.Parent = rightArm
iCopy.Parent = leftLeg
iCopy.Parent = leftArm
iCopy.Parent = headfoil

Well, wahat are you doing in fact? Since :Clone() returns the copied object, the script will turn game.ServerStorage.DFDIllness:Clone() into the copy new location. The parent is nil

When you are doing

local iCopy = game.ServerStorage.DFDIllness:Clone()
iCopy.Parent = torso
iCopy.Parent = rightleg
iCopy.Parent = rightArm
iCopy.Parent = leftLeg
iCopy.Parent = leftArm
iCopy.Parent = headfoil

you are moving the part to the torso, then to the rightLeg, rightArmand etc. You are JUST moving the object between parts, which doesn't look your purpose. What you want is to clone every part and put it on every parent. So you will need to call :Clone() 6 times:

local iCopy = game.ServerStorage.DFDIllness
iCopy:Clone().Parent = torso
iCopy:Clone().Parent = rightleg
iCopy:Clone().Parent = rightArm
iCopy:Clone().Parent = leftLeg
iCopy:Clone().Parent = leftArm
iCopy:Clone().Parent = headfoil

Hope I helped.

All of those extra assignments to iCopy.Parent are redundant. That may be part of the reason that your code isn't doing quite what you expected.