It is very distressing for you when something threatens the health of your beloved pet. i lost my last two collies to cancer aged 13 and 12. My present collie has a lump but I took her to the vet and they aspirated it and it is only fatty tissue and harmless. Perhaps you could save yourself some worry if you got Delious checked out. I know it is a big thought to take this step but you could be worrying for nothing.
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