Will sharpies work (and stay) on the transfer design

[grumpy's fan]

I want to make a pillowcase using transfer designs for my DD birthday with the princess lunch and am wondering if anyone has had the characters sign the actual design for them and if it will last???? I'd like to have all the princess sign their section of the pillowcase that has their design (there won't be any space left with cotton pillowcase material as all the designs take up the entire pillowcase!)