In addition to whatever sink/drain problem you're talking about, that saturated ring on the subfloor around the toilet suggests you have a leak between the toilet and the closet-flange, though it could also be a leak elsewhere like the tank to bowl gasket that trickles down to the base of the toilet.
Leaking around the flange is usually from someone installing thicker flooring ( say going from linoleum to tile ) and not bringing the closet flange up higher, a rusted out closet flange if it's older construction ( newer ones are usually plastic ), and/or not using the proper thickness of bowl wax.......
Also an otherwise good setup can develop a leak if the toilet isn't fastened well: if it is loosely mounted and allowed to rock/wobble it will probably disturb the wax every time it wobbles, and eventually start leaking. The problem you can run into here is even if your flange is at the correct height and you use the proper bowl wax, your subfloor is already water damaged and turning to mush, so it will probably be difficult to fasten the toilet solidly without repairing the subfloor
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o I decided to walk over to them and I asked her " how was the meeting today darlin? " she looked at me and said " it was good, I'll tell you more about it when we get home in a few ". I replied with " wonderful I'll pick up your favorite for dinner".
The two guys left in a hurry and she told me " you have no idea how much that meant to me .... thank you." I said "you're very welcome ma'am .... you can never be too careful. "
I made sure the guys left before I walked back to my car and as I was walking back all I could do was think " I hope a man is my future daughter one day
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