Update on Mom is that the pneumonia is back and along with it is another complication. Mom isn't getting deep enough breaths in and out just with the oxygen mask on. Because she's not getting enough of the breath back out, carbon dioxide (CO2) is getting left in her lungs. The CO2 is then combining with water (H2O) in her lungs making carbonic acid (which if I remember correctly from my high school chemistry class is H2C03 with the chemical equation being H2O + CO2=H2CO3 *thank you Mr. Cline*). From what I understand, the lungs always have some carbonic acid in them as a biproduct of breathing--she just has it in excess because she's not getting enough of the CO2 back out.
So, bottom line is they have to put the ventilator back in so they can get gunk out of her lungs. Will keep everyone posted as I am able. Thanks for the thoughts, prayers, etc.