Even though I often didn't see my father for months at a time, I know he loved me as much as I love you, Son, and as he once said to me, 'I may not be the best father, but I will always send my prayers when you need them the most,' and that is what I intend to do for you. Remember this, even if you don't see me for a while and want to hate me, I love you.
When was the last time a character caught a cold or flu? Real people get them every now and again even with solid heating and dry interiors. Your characters are out in the cold and wet, and even inside is not always dry and warm. Imagine having to stop your dungeon crawl, sitting in a tight defensive position, while you all are feverish.