Wee problems 6yr Lab

Hello all, I'm new to the forums but have come with a problem with our 6yr old chocolate Lab.

She has this unusual behavior and has had it for as long as I can remember.
She was slow in toilet training but now that has been solved she has a tendency after a wee of then rubbing her tail into it then licking it off.

Almost like she is trying to remove evidence of a wee.

Any thoughts on why and how we could stop it from happening?

Thanks.

get her checked out at the vts just in case there is an underlying medical problem