Pick

I'm staring at the back of Maggie's head and notice that she is either sucking on her finger or picking her nose, both of which are habits we're working on breaking.
"Maggie, is your finger in your mouth or in your nose?"
"Oh Mom, I'm just trying to get that booger out of my nose," and she rolls her eyes slightly.
"Oh. Well would you like a tissue?"
"Yes, that would be better. So I can get that booger out of there." Very logical.
I grab her a tissue and hold it while instructing, "OK, blow!" She gives it a good strong blow, but...
"Errrgghh... it's still in there!"
I leave the tissue on her lap, just in case she wants to try again, and not 15 seconds later she thrusts her index finger three inches in front of my face triumphantly and says, "I got it!"
To which I reply, "Argh! Gross!!!"
To which she replies, "Yeah, gross!"

She knows it's gross, that's a start.