More: Tango found a tennis ball in the garage. It's been his non stop obsession ever since. That was 3 years ago. He'll take any tennis ball, but his favorite are the slightly larger and softer "training balls" for kids learning to play. He picks one ball to play with for the day and you better keep an eye on it, because if it's lost he mopes and whines and drives you crazy for the rest of the day. He will not take another ball until tomorrow