Olive - we took some drastic action at ~ 18m which involved some long term medication. This is not for everyone and involved lots of thought/research but did fix things up. My GP is awesome so I was not unhappy with her reasoning rather frustrated at the anxst we were all going through. I have a great ENT who I rang to ask some questions and he was excellent too (he took my tonsils out a few years ago and is a surgeon who seeks alternatives to surgery rather than be overzealous). I did have a friend whose son was the same age and had grommets inserted several times.
She has had no issues since, well ear related, lol! Good luck!