Our home is built on a concrete slab. We build it that way because of poor drainage on the lot. It is a two-story home.
We put in a small bathroom on the first floor with a sink and commode.
All of the plumbing is centralized. Now, we want to remodel the small bath downstairs and add a shower; however, we do not want to have to break up the concrete to put in a drain for it.

Is is practical and/or probable to tie in the drain for the walkin shower to an existing pipe which carries out the water from the sink and/or washer which is also downstairs.

What do you suggest?