Just back from the vet. Her skin was red and inflamed last night, which I was pretty relieved at coz that would suggest an infection rather than something more sinister.
I phoned the vet and he wanted to take a look at her this morning.
He thinks the "mass"
is moving down her leg a bit and is smaller and a bit softer. He admitted thoday that he initially thought it might be a tumor, but said that even if it was, it should be much easier to cut out based on how it looks today.
He is pretty sure now that it is an infection - although still no sign of an entry wound and I am worried that a foreign body might be in there still.
So, she's on antibiotics now, which I hope will fix her.
Poppy is missing her on our walks, and when I take Bramble to the vet, I can hear Poppy howling at being left in the house. I knew they were close, you don't realise just how close until something like this happens.