I can only add to what the others have said regarding your Bayley. My Auburn had similar issues in her last 3/4 year. The only thing I thought to mention, is if your guy is on any arthritis meds that have recently changed it could also be contributing to the gagging. My girl was on Rimadyl in her later years, but as it started not helping as much she was switched to Metacam (?). She had a really hard time with that medication, and the queasy, gagging did not show up until some weeks later, she absolutely could not tolerate it. Putting her back on Rimadyl solved a lot of the gagging which had to do with medicine intolerance.
Just a thought in case it applies in your case. Best wishes to you and your Bayley.
Litter announcements / solicitations are by approval of the Administrator/CoAdministrator- only.