Royse City Engine and Tanker 81 responded with RCFD Deputy Fire Marshal after being requested by Caddo Mills for mutual aid suppression, water supply and command. Members from Cash FD also responded to assist. Companies arrived to find a fully involved out-building that was threatening exposure to the main house and a travel trailer nearby. Caddo Mills Engine 1 made a knock down on the main body of the fire with their 1000gal tank and were able to hold the exposure risk until Tanker 81 could resupply them with an additional 3500gal