Top: the direct orbital histories for four galaxies in our sample spanning the range of 2 Gyr into the future and going backward to 6 Gyr in the past. Present day is denoted with a dotted black line. The left panel shows orbits relative to the MW, while the right panel shows orbits with respect to M31. The black and gray dashed lines indicate the virial radii of the MW and M31, respectively. The four galaxies pass within the virial radius of either the MW (for the case of Leo I, Leo II, and NGC 6822) or M31 (for IC 10) during the 8 Gyr time period plotted, suggesting that these galaxies may be considered interacting or backsplash galaxies. Bottom: similar to the top panels for the remaining eight galaxies in our sample, but showing only the past 6 Gyr and with a more extended vertical axis. These galaxies are all on first infall into the MW and M31, as the have either never crossed the virial radius of the MW or M31 or have only crossed it very recently.