Homemade Alternative to Scotchguard

My husband and are are going to reupholster our dining room chairs, and since we have 2 kids under the age of 4, we'd like to pretreat the fabric to make it more stain repellent. I don't like the idea of a chemical fabric protector like Scotchguard, so I'm wondering about the alternatives since I won't be able to just take the covers off and wash them!