I've suddenly remembered something.
A few years ago there was – it existed for several years – a set-up in Southsea that called itself Southern Sophistication. Later they were located on the northern edge of Southampton. The "workforce" consisted of a very, very shy BBW of about 20, her mother, and a second woman who was also of mature years. I never met the SWWWAOMY, but it was the mother that opened the door and welcomed visitors, and I'm in no doubt that she was indeed the mother. The "dynamic" was unassailable.
On one occasion when I was visiting the daughter I was offered the opportunity to have the mother join us. But – like, indeed, the young BBW – I'm very, very shy, so I stuck with a one-on-one session.