Spit tacks

I was looking for a fan that I have asked Lon for several times. I finally found one, not the one I wanted, but one. The more I got to digging, the more frustrated I was getting. Landon found me in this state and asked what it was that I was doing. I told him I was so angry at the moment that I could "spit tacks". What are tacks? Why do you want to spit them? Do you want me to get some tacks so you can spit them? No, I'm OK for right now. A few minutes later he comes up to the side attic, climbs over all the stuff/boxes/junk and hands me 3 clear thumb tacks. "Here Mama, here are some tacks for you to spit." How can one stay mad and not want to burst into out loud laughter? Oh the innocence of a 6 year old...just wanting to help.