Can I break our lease?

I moved into an townhouse with my wife and small child. The pamphlet and website say "small pets welcome". The lease clearly indicates that dogs must be no larger than 15 inches in height and 20lbs in weight.

Our neighbor has 3 dogs much larger than this. One dog is very aggressive and comes at us when we are in the back of the townhouse. This is worrisome in regard to our small child.

The neighbors also let their dogs' chain extend to our "rental property line" in front of the dining room windows where they defecate. Now imagine 3 large dogs defecating in front of your window and urinating on your air conditioner every single day. I called and sent 4 emails over the course of 3 months because we have been unable to open the windows in the dining room due to the smell of feces. They told us that they have spoken with the tenant but there is nothing else they can do. I would like to break the lease. What are my rights?

[sunlover]

You cannot break lease under these conditions. You can ask to be released from lease or relocated to another unit

If the lease says only small dogs but they let large dogs populate the propery, wouldn't the management company technically be violating the lease?

[sunlover]

You do not know the terms of other tenants lease nor is that a valid reason for "you" to break your lease. If you have Health concerns you can contact your local Health Department