I will try to make a long story as short as possible!

A few nights ago, we started hearing a bubbling noise in the toilet downstairs. It stopped, and the toilet was flushing fine, so we shrugged it off. The next day, my daughter was doing dishes upstairs. She must have let the sink get too full and let the drain up for a little bit then put it back. I heard the noise again, and ran in and saw what appeared to be some dish soap in the toilet. So I had her pull the drain again, and sure enough, dish soap filled the toilet.

Plumber able able to make it two days later, and at that time, everything seemed to be working fine. He ran some water, had me fill kitchen sink and drain, with and without dish soap and in the end he said everything was fine, my daughter had probably just used too much soap.

So, yesterday I was just finishing up the dishes and washing the counter top by the sink and when I got to just a certain spot I thought I could smell something. So I opened the dishwasher (which I never use), to find a pool of standing water. I thought MAYBE it was possible my five year old had hit the button and started it then stopped it, so I just reset it, watched to make sure everything drained fine, which it did, then put a tablet in to clean it and ran it one time. It seemed to work just fine.

So I ran the sink water on both the regular sink and garbage disposal side and watched and it all seemed okay. Then, I filled the sink up with dishwater and drained it, and it seemed okay until a few seconds after draining, a little water seeped through in the dishwater.

The plumber never went into the kitchen. He went to the utility room downstairs, checked the main drain and said that is fine, felt the line from the kitchen, said that's flowing fine and ran water downstairs and flushed the toilet.

If the kitchen line downstairs is fine, could the disposal be clogged even if it appears from the sink to be draining fine?

Your had a blockage in the main drain line. It was a partial blockage, not a complete blockage. Drain water could get through but it took some time. Fortunately for you, that blockage was also temporary.

A few nights ago, we started hearing a bubbling noise in the toilet downstairs..
That means that the blockage was after the toilet downstairs. When water was run in the kitchen, the water going down the drain pushed air in the pipe back up through the toilet.

It stopped, and the toilet was flushing fine,
That means that the blockage was a long way from the toilet. There was enough room in the pipe between the toilet and the blockage to hold the water from the toilet. Had you flushed the toilet a second or third time the toilet would have over flowed.

I heard the noise again, and ran in and saw what appeared to be some dish soap in the toilet. So I had her pull the drain again, and sure enough, dish soap filled the toilet.
This time the pipe between the toilet and the blockage was filled with water and the water from the kitchen had no where to go but into the toilet.


Plumber able able to make it two days later, and at that time, everything seemed to be working fine. He ran some water, had me fill kitchen sink and drain, with and without dish soap and in the end he said everything was fine, my daughter had probably just used too much soap.
Means the plumber was honest and didn't invent some reason to do something to increase his bill. As said earlier the blockage was temporary, meaning that by this time the blockage had cleared itself.

I don't agree with his "to much soap" logic. The water in the dishwasher is a different problem. I am willing to bet you a pizza, that you don't have an Air Gap for the dishwasher. An Air Gap would be a round knob (usually chrome) with slots in it, on the kitchen sink. It prevents water from the sink draining into the dishwasher.

Some places require an Air Gap some don't. If an Air Gap is not used you must use a "high loop" in the dishwasher drain hose.

Look under the kitchen sink, you should see the drain hose from the dishwasher connected to the disposal. That drain hose must go from the dishwasher up as high as it can and then down to the disposal. Yours probably comes into the cabinet down close the bottom of the cabinet and then up to the disposal. Water from the disposal can flow down that hose and into the dishwasher.

The correction for this is quite simple To create a "high loop" in the dishwasher drain hose, put a screw in the side of the cabinet, up as high as you can. That screw must be above the bottom of the sink. Then take a piece of nylon cord and tie you dishwasher hose to it. That will prevent water from the sink draining into the dishwasher.

Are these guys here great or what?