I've read a discussion or two on the subject by amateur astronomers far more knowledgeable than myself. The clear consensus was that it's quite unlikely. As I

I've read a discussion or two on the subject by amateur astronomers far more knowledgeable than myself. The clear consensus was that it's quite unlikely. As I understand it, the general reasoning is that multiple star systems, even those which are quite far apart by multiple star system standards are still so close together that if we had a partner in even the high end of that observed range it would be easily detectable. Also, if the partner were so far away as to be hard to detect it would be exceptional and have an orbit in the hundreds of thousands to millions of years, not a mere 20,000.