I have 2 yr old twin boys who never fail to out so me. We have recently listed our house for sale and I was try to do some touch up painting. I have never had this problem with pen before but I can not get it to not show through the new coats of paint. I have also tried primer both Kilz and Bullseye and maybe I am just not doing something right but it is still showing. I also have black sharpie on one their bedroom door and and worried the same will happen. Any advice would be greatly appreciated. I have an open house on Saturday.

Try Zinzer BIN.

It is a pigmented shellac and is considered the best stain killer primer.

Where can I find it?

You should be able to get it at place that sells paint. It should be right next to the Bullseye, Kilz, and 1-2-3.

You do not want to use BIN as it is alcohol based and so is the sharpie and as such it will cause it to bleed back through the primer. You need to use a stain killer such as KILZ Oil Based or CoverStain to seal the ink and sharpie in.

Help! Did anyone ever find a solution for this? I too have sharpie on my wall and cover stain isn't coving it.

The stain kiler needs to be applied lightly so it will seal in the marker and this means you will have to apply it a couple of times to seal in the marker. The oil based stain killer should work best on sharpie but you may have to use both to seal it in. But bear in mind the primers do not cover well but they still will seal in the stain as they rely on the finish paint to do the covering/hiding.