Marly is a cutie! My girls are also 16 weeks old, and we're "getting there". Gertie is better than Ida, but then Gertie has been with us a lot longer. We brought Gertie home at 6 weeks old, but didn't get Ida til about 11 weeks old. I'm having a better time now that it's cooling off, which I know this wouldn't help you with the apt. situation. They're just staying out longer and it seems to help with the idea that they don't go in the house. It sounds like she is making progress.
There is nothing nicer than two sweet Bully girls, unless it's THREE sweet Bully girls!!
Julie, Gertie, Ida & Clementine in Az.