Forget magicians, ponies or face-painting. Nothing says happy birthday like a foul-mouthed grandpa driving a fully loaded, shiny black, fast, ultra-performance two-seater completely un-child-friendly Chevrolet Corvette convertible. When my kids were small, this was how we did birthdays. Everyone wanted an invite. We heard it before we saw it. Like fireworks in reverse — engine roaring to make a grand entrance, the Corvette rounded the bend toward the house, Grandpa