Okay this is a rant. A rant about Poo. Yes

We have a dog. A miniature schnauzer, who is a bit over 1 year old. We live in a town home and our yard is shared by other tenants. Ripley is walked every day and I always have my pooper scooper or a plastic bag to pick up after her.
We have a neighbor, who we call "Cat Lady." Why? She lives by herself, has at least 3 indoor cats - that I've seen - and feels it's her civic duty to take care of all the stray cats in the area by leaving food out for them everyday.
Cue the Law and Order noise.
Today, Saturday May 31st. 10:30am. I took Ripley for a walk around our block, plastic bag in tow. Ripley did her thing, I did mine. Aaron and I left at 11am to head to the Jeep Dealership to turn in my leased car and get a new vehicle. This took us almost 3 hours to do. After that, we had to race 30 min North for Aaron to get to his hair cut. This took just under an hour. We still have a few more errands to run, but we want to check on Ripley since she's been alone most of the day.
4:30pm we get home. I feed her and take her out back while my hubby is messing around with the new gadgets in the car. Ripley pees quickly because she is focused on a possible ride. I wanted her to do #2 but she ignored me.
I walked down the sidewalk that's in the back area and noticed old, dried out poo by another neighbor's house. I don't want to say I'm a expert on Poo - but it looked like cat poo to me. Not to mention there were 3 cats hanging around our place in the morning, so it's possible. (I'm not bashing all cats - I had a cat - I know they bury their poo, but not always) The one thing I can assure you, it was not our dog's mess.
Seeing that we were running short on time, we had a friend coming over around 6:30pm to watch the Stanley Cup Playoffs which started at 7pm, I quickly picked Ripley up and took her for a walk around the block - yes bag in tow again. She didn't preform this round.
We put Ripley in the house and head off to finish our errands. We were gone less than an hour when we pull up to our garage. I noticed the neighbor girls in their garage what looked to be vacuuming out a car. Aaron waves as he opens our garage.
I get out and I'm hit in the nostrils by a horrible, but familiar, odor. It's POO. I check my sandals, nothing. I take a few steps to see where the smell is coming from and there are turds right in front of our garage. I begin cussing cats up and down since they like to hang out in front of our garage door when Aaron comments that it looks like it was thrown at the door. Looking at it again - he seemed to be correct. We both start pondering which one of our neighbors could be so &#@^%.
As I scoop it up to dispose of it, I notice the poop I had seen earlier was gone from the one neighbor's house. My mind starts racing back to the time I ran into the Mother of the house who once told me her younger daughter was playing in the back an stepped in poo. I told her that I was sorry to hear that about her daughter but we always pick up after Ripley. After all, I have been a victim of stepping in poo before and I would alway get pissed off at our neighbors who let their dogs roam in the yard, crapping where they would want to crap and not picking it up.
I then realized how "friendly" the older daughter was. I've ran into her early in the mornings when taking Ripley out. I alway greet her with a friendly "hello" or "good morning." She just scowls at me and heads into her house.
It didn't take long for me to put 2 and 2 together and it became obvious that it was the daughters who did this. Though I am giving the parents credit that THEY (Mom and Dad owner) would say something to us AGAIN if they ran into the poo and not be so passive aggressive.
Not to mention that we are commented by even our strangest of neighbors that we are one of the very few in the area who even pick up after their pet.
I wanted Aaron to go over to the girls and rip them a new one, but he chickened out. I would have gone over myself but I kind of realize that the girls aren't adult enough to handle an adult conversation and would probably be better off talking to their parents. The only thing is, they are the type of neighbors that we don't see on a daily basis. : /
The retaliation side of me wants to import my friend's dog's poo (a Boxer who takes human size dumps) and write on their driveway - "DON'T MAKE ASSUMPTIONS."
I really want to say something to this family but I don't know the best way to inform them of their immature daughter(s). I thought about leaving some type of note but I'm worried that Poo Throwers may intercept the note. What do you think?
Yes I do realize this is a funny story, AFTER the anger emotion. But tell me, would you enjoy someone throwing poo at your property? And sorry if I grossed anyone out.
Everybody Poops.