Allergic to snow?

I love the kids and their theories on what they may be allergic too. We know that Joe is convinced he is allergic to Pineapple hahaha thats ok...thats easy enought o avoid. Today though Molly decided she thinks she's allergic to snow. Why does she think this you ask?? Because for the past few days she has mentioned her head hurts her...and it just so happens she has been out playing in the snow these past few days! Sunday was sledding, yesterday I took her out to color the snow with water dyed with food coloring and today we had to go out to her preschool conference and Nick pulled her in the sled a little bit before dinner. Who knows maybe it's the air pressure or something I know Paul gets headaches from that sometimes.