Colleague makes work more difficult for bartender

DEAR HARRIETTE: I am a bartender, and I have a colleague I work with about four times a week. He is a nice guy, and we generally get along well, but there are some aspects of his behavior and work ethic that are becoming increasingly difficult for me to handle. While he is friendly and personable with customers, he often lacks the professionalism needed in our line of work. He frequently arrives late for his shifts, leaving me to handle the early rush on my own.