I'm just curious what the ideal age gap between dogs is. With Rotties, it's usually suggested that you wait til your current dog is 3, but Rotties are very slow to mature and have different temperments. (Harley is almost 6 and I swear he is just now filling out completely.) Two puppies at the same age sounds like way too much trouble to me, but is 6 months okay, a year? Should you wait til the first dog is completely mature?