Hi I have a kitchen sink, with under the counter vent stack, a Pro-Flo, I also, on the same side of the house, have a bathroom with again, an under the sink vent pipe... Does not happen often, but since having house built.. Toilet in bathroom will not send the water down when flushed.. When I plunger it, water is pushed up through the bath sink, and shower stall... When I turn on the sink faucet, toilet will bubble... Also, when dishwasher discharges water, toilet again bubbles... I'm not sure about theses under sink stacks.. Is there away to blow out these vents? Or is this an expensive job for a plumber? Thanks

When I turn on the sink faucet, toilet will bubble... Also, when dishwasher discharges water, toilet again bubbles.Sure doesn't sound like a vent problem. You give a classic description of a blockage,
You have a partial blockage downstream from the toilet that bubbles that mist be snaked.
This can be addressed in several ways.
1- Pull the toilet and snake from there, **or**
2- Snake from the lavatory roof vent, Put out enough snake to reach the base and 16 more feet. Good luck, Tom