He’d stopped bothering with his birthday. Who was there to care anymore now that he was all alone? Alone, that is, except for Buster, his dog. Buster was also getting on in years and, like the man, had not many more birthdays left in him.
The rattle of the letterbox and the sound of items falling to the floor roused him from his reverie. One item caught his eye, something that was unmistakably a greetings card.
Upon opening it he read “Happy Birthday from Buster (with help from your big sister.)"
Big sisters never forgot birthdays, however old you were.