You should have their name, etc. Were you out somewhere with the DS? Any teenagers around? Maybe someone had guests over? There are all kinds of explanations, and they had to have been within 100 feet- (that's the max range stated on the websites, but my kids say it's more like 6 feet!)
So unless you're in a high rise, it was probably the next door neighbors.
We are not in a high rise. And no teenagers around. The Nintendogs website said the range can vary on weather conditions.
>>>it was probably the next door neighbors.
There are a few homes that would *not* give me comfort that could be in range.