Pillowcase - Markers bleeding through?

[TheTexasGal]

For those that have done the pillowcase signatures - did you have an issue with the markers bleeding though to the other side? Did you put anything in between your pillowcase to keep this from happening?

I am thinking of buying the STAINED markers by Sharpie that are brush tip markers made to resist fading when washed. I am concerned that they might bleed through. I am thinking of putting a piece of posterboard or file folder between the pillowcase but I am concerned that this will make it a pain to pack.

Any thought? Thanks!