Apparently, it originated in the Alps, and was started by a young hiker . This virile young man spent the night in an Alpine lodge, where there were also several attractive ladies, relatives of the proprietor. After a number of nocturnal dalliances, the young man set off early in the morning, only to be be berated by the irate chalet-owner, who shouted across the valley " You Bastard !! You seduced all three of my daughters, and my sister ! "
Whereupon the young man turned, drew a breath, and yodelled " And your old lady too ! "