Please No Poop

The other day we went to the uptown art fair and met up with some friends of ours. They have a girl that is a few months older then Back Seat Girl. We had a good time. A long day of walking and playing in the park.
On the way from the art fair to the park we were in our old neighborhood. It was nice to be in our old stomping grounds. A few things changed but it was mostly the same. We went to the "triangle park" where shotgun and I used to stretch after going for a run around the lake. This time around things were different. We were with another couple and their kid. We mostly just played and watched the kids play.
Anyway, on with the poop you say. In our old neighborhood there was a garbage can on the street in front of a pretty nice looking house. This isn't that odd and the can was just your standard City of Minneapolis garbage can. However, this one had a unique message spelled out on it....




So many questions. What made this person put this sign up? Is this an ongoing problem? What kind of poop?