Recently one of our toilets has been bubbling when another is flushed. The other day my washer also backed up when it was emptying (I ran the washer twice since that and it has not happened again).
We were told to make sure there were no blockages in our air vent. So last night we put put the water hose in our air vent and turned it on, this only caused water to start backing up in our bathroom sink.
Any suggestions?

Hi sunshine and welcome to The Plumbing Page at ANHD.com.

We were told to make sure there were no blockages in our air vent. You were misinformed. Bubbles indicate a blockage while gurgles indicate a blocked vent, You have a partial blockage downstream from the toilet that's bubbling that must be snaked and cleared. This can be done by pulling the toilet or by snaking from the lavatory roof vent. Put out enough snake to reach the base and 16 more feet. Good luck, vbTom