Reba McEntire and boyfriend Rex Linn sure seem like a perfect match! As if the country superstar's romance with her "CSI: Miami" alum beau couldn't get any cuter, the couple revealed their nicknames for each other in a sweet back-and-forth on Instagram. Rex started off with a snap of him and Reba kicking back on a relaxing day in the shade, calling her his "Tater Tot" and adding red heart emojis to his caption. So far, so adorable…but Reba took it up another notch with a post of her own, sharing the same pic and letting fans know she was enjoying a getaway to Montana with her