Water comes through ceiling in all bedrooms about 2 hours after the family showers

Need more info. Is this a shower stall or tub?

What is finish on walls in shower area?

Are there any cracks between wall finish and tub/shower?

To check if drain is leaking, run water into tub/shower without getting water on walls. If u do not get a leak then water is going through water finish.

Chuck

One question! Tub or shower? If shower is it a custom tile or plastic/ fiberglass shower base and enclosure? Back to you, Tom