Along with sprays, I use a candle which I bought in Value Master. It's simply called a Mosquito candle and if I remember correctly it's in a yellow and green tin in the first isle on the right as you go in. It smells like lemon and has lemongrass in it. You can burn it inside or out. I find it is fantastic. Another thing you should check is that there is NO sand in their beds at all. It means having a shower before they go to bed and making sure their feet are sand free. The sand flies can be in the sand you bring home.