Preferably Virgil or Shakespeare or something that will teach her to consider people other than herself.
It’s likely none of you need any admonition to avoid acting like the tremendously self-important Casey Nocket, because you’re smart and decent.
There are, believe it or not, people (including supermarket birdcage-liner Cosmo) defending this gal and her suspected vandalism of National Parks, including family members who refer to her as a “good girl“. Strangely, I find myself wondering how one can so badly screw up raising a female that she thinks finger-painting national monuments with difficult-to-remove paints is at all something one can rationalize doing, much less consider acceptable or defensible—to the point of signing your name to each ‘artwork’.
Don’t be a self-important screwball like Casey. If you want to paint, buy a canvas from the craft store. Heck…aren’t there walls in your home? That should work. Go bananas!
So far as Casey, she ought to be prosecuted, pay any applicable fines, and ordered to clean up these defacements on her own dime. Throw the book at her. Why?

Courtesy ModernHiker.com
She’s so very proud of using acrylic instead of, say, chalk—this was an intentional effort to “make her mark”.
And remember, when partaking of the beauty of creation, the only mark you should leave is your footprint.
More at Calipidder (along with Modern Hiker, the first to break this stomach-turning story) PetaPixel & CTV News. There’s an NPS press release, a petition to the White House asking that she be prosecuted to the fullest extent of the law, and reports that Nocket is talking to the NPS.
Hmph.
Oh my gosh! I agree, throw the book at her!!!