How long will Permanent Marker Stay on Shirts?

I am attending a David Cook concert shortly and if he comes out before the concert I want him to sign my shirt, it will most probably be permanent marker...It's a creme colored shirt so it will get dirty and I want to wear it on occasion. Will the marker come wash off? Any hints to washing it so it will stay on for long as possible? Cheers!

it will only stay on as long as you don't wash it, I suggest you have sign in a washable marker it lasts much longer on clothers

My son has a shirt that all of his classmates signed last year on Field Day that he wears every one to two weeks and I wash it every time (I have to he's a typical 9 year old boy), the marker is still there they used Sharpies, but I would buy a laundry marker or a fabric marker and try not to wash it too often, because it wil fade a bit.

Permanently!*bows for the brilliant answer*Seriously, the marker will always be on your shirt as long as you don't wash it in bleach (which you probably wouldn't because it's a creme shirt). Everyone is right though, it will fade after every wash, but if you use a 'color safe' detergent, it will stay stronger, longer.

along time