Water damage

I would  like to start off by saying that my family and I are truly blessed and are grateful for what God has done in our lives. Recently we bought a house and moved to our dream location near family. However, one evening when I got off of work. I realized that the upstairs sink had been leaking throughout the day and over the course of the day. Water managed to make its way through the floor of the upstairs bathroom and hallway through the down stairs ceiling and running into the floors, causing damages to the ceiling/walls, floors, base boards etc. We did our best to fix what we could but there is still more work to be done. We also recently noticed mold beginning to grow on the ceiling in the bathroom and hallway. While we contacted our home insurance agent and made the appropriate follow up calls, and from my understanding they will not be covering any damage because  the policy wasn't in effect yet. We would appreciate any help that you can give.

Thank you