So I moved the sink out of the way and cut a hole in the floor to find the breaks in the pipes. Three of the pipes were broken as well as some fittings.
I removed all of the copper pipes, then started in the basement and ran all new 1/2 inch CPVC pipes. OOPS! I had to open it all back up and put in a new drain to the sink..
Then we replaced the drain to the tub as well. this required cutting a slot into the wall. You can see the water damage in the discolored wall paper.
The new drain pipe runs all the way down to the basement. We covered it with new 3/8 inch sheet rock so it all looks great now.