Someone explain this to me?

So i have been slowly spring cleaning my house.
Now i went through haiden and logans toy boxes, closets and tossed things in the trash, put the pens and markers that i found back where they belong. I went through my blankets, sheets closet as well took pens and markers out of their, as well as their bathroom.
But the last few weeks i have been finding new pen mark and marker marks on my wall, their walls, and end tables.
So today i walked in logans room and saw pen scribbles all over his wall but no pen to br found as i looked everywhere including underbeds. I cleaned his wall off.
Someone explain this issue.

    Oh dear. I wonder where the pen is... because he must have one!!!!
    About Ashley
    Birth: March 23
    On since: Mar 6, 2014
    I am 25year old stay at home mom of 3boys. I am also married.