Furry Gall?

I have no idea what is going on here.  Interested to see it is starting to grow through the adjacent leaf.  Is it growing round  leaf or a rosehip? - we think that might be what's in the middle.  Definitely one for Tiny Tuesday. And sure someone on Blip will know what this is. Spotted on our regular Tuesday walk . 6 of us but no one knew what it was.