The brutal snow and coal shoveling of the 1944 winter has a taken its toll on my grandfather's knees. After decades of climbing all those stairs to bring down trash and shovel snow, he's torn probably the ligament in his right knee.
Frank's mom wrote to him about his father's severely infected knees. Frank writes these two very short letters, the first to both his parents, the second, about two weeks later, just to his dad, my grandfather. In an earlier letter, my grandmother had written to Frank (Ebner) telling her son of Grandpa's knee injury. Here I think Frank is just trying to establish a personal communication with his father so he can encourage him in the future to take care of himself.