My daughter had 3 labs. One had to be put to sleep 18 months ago. The second oldest one is completely blind with cataracts and is a bit on the portly side but her tail is always wagging and she doesn't have any trouble finding her way round the house and the youngest is about 7 now and she is a total lunatic.
One of the reasons we never had pets.
We kept fish for 30+ years but its not the same when they die