Sadie has had one almost every year...usually late fall or early winter. In fact, I just took her to the vet today cause one was coming on. The first one she got, when she was about a year old last for months and eventually she had to be put under and her ears cleaned really good and deep ( Like Pam mentioned). Since then, we can tell almost before she gets them and get her started on the meds and they clear up before they get too bad.