twelve slobbering dobermans.
Jackie, great game, can't wait for the most apposite. http://kidexchange.miningco.com/kids/kidexchange/cs/twelvedays/ and http://www.pncbank.com/12days may give you some ideas on this. I came across one of those last year and the other when I googled to find it.

Trying to find lines that matched slightly with the original I had:
Eleven plumbers piping but instead chose:

Twelve slobbering dobermans
Eleven voyeurs peeping



Rod