The first-principles-based analytical method for predicting drop size distributions in sprays developed in our previous study, and used to investigate the influence of separate fluctuations in liquid physical properties and gas-liquid relative velocity on the drop site distribution, is extended to study the impact of simultaneous fluctuations on the drop size distribution width. Fluctuations of two types are considered: those in gas-liquid relative velocity and those in liquid physical properties. These fluctuations are represented by joint probability distribution functions (pdfs) of velocity-viscosity, velocity-surface tension, and velocity-density. Results demonstrate that combined liquid physical property and velocity fluctuations can lead to drop size distributions significantly wider than those resulting from velocity fluctuations alone. For combined velocity-surface tension fluctuations, this widening is significant over a range of mean velocities, whereas for combined velocity-viscosity and velocity-density fluctuations, the widening is significant only at low mean velocities. Finally, it is observed that the drop size distribution remains almost unchanged for liquid physical properly fluctuations less than 1% (RMS/mean) over wide ranges of mean velocities and velocity fluctuations. In such cases the drop size distribution can be predicted satisfactorily by considering velocity fluctuations alone and the expense of using joint pdfs can be avoided.