Mud is 18, so I expect health problems. She is on prescription food and medicine for a thyroid condition, but she's been healthier and happier the last couple of years, since going on the meds, than she had been in probably a decade.
Despite that, every yearly check-up is cause for alarm. Last year I was scared to take her in, but this year I was pretty confident that things were going well. Then the doctor told me that she had a tumor -- a somewhat large one -- in her belly. Since Mud is 18 and is showing no symptoms (although she lost 1 lb in the past year), the doctor recommended just leaving things be. We have no idea how long she has left, but every day for the past couple of years has seemed like an extra day with her to me. I just hope there are many good days left for her and that she feels happy and comfortable through them all.
Mud has been with me longer than my daughter and husband. When we do have to say goodbye to her, it's going to be terrible. She was with me through some lonely, difficult years in my 20's and she is a wonderful companion.