This is a birthday card I did for my niece who celebrated her eleventh birthday last week. When she was ten I drew a pic on her card with the number '10' as a balloon - and I drew my son, who had his first birthday a week later, holding onto the the '1' balloon and floating away. The image depicted my niece shouting at him that it was her birthday, and that his was the following week.
She didn't like it. She felt it cast her as being a mean cousin, shouting at the little guy. Tough clientele. Back to the drawing board, and no unintentional implications in the above.