Why oh why?!!

We just can't seem to win when it comes to owning a dog! While Dennis and I were in Mexico, Lacy attacked another dog. Ethan was playing basketball in the backyard and thought it would be okay to let Lacy off her lead while he was right there with her (thanks to his father doing the same thing, against my wishes-just had to get that out!). So of course, while she was free, an older man went walking past our house with his little dog (who was on a leash) and Lacy bolted before Ethan knew what was happening. The little dog was hurt pretty bad and the man was bit. This is the second "recorded" incident with Lacy girl. She also tried to attack another little dog who entered our backyard. Luckily she was on her lead and couldn't get to him very well, and I was there to step between them. This wasn't reported because he was a stray and Lacy didn't get him. There's also the time that Ava pounced on her when she was sleeping and Lacy bit Ava on the face pretty bad. We know it was because she was startled because she came over afterward and loved and kissed Ava over and over again. (Ava was never scared either-went right back to putting her face right on Lacy's and kissed her back). But all of these incidents have made us think it might be best to put Lacy to sleep. We definitely don't want her to go back to the pound-we love her way too much and fear she will have a horrible life with such a track record. I really hate the idea but I told the kids we need to have the courage to do what is best for Lacy. Next week will be so tough for our family!! (Ethan has especially bonded with this girl!)