Hi Jocelyn, I was so excited about the India connection that I didn't take in the Waite possibilities. That is where I am going next although being a parent during a school holidays is cramping my style. Tomorrow I am off to the Harry Potter studio tour with my daughter and will have to switch off from research and concentrate on magic - strange life, but I will find Sibbella's background if it the last thing I do and now I have some new leads to follow. My sister has Sibbella's locket, my aunt has her brooch and we have an oil painting of her but no information about who she is.
I will tell you if I find anything. I hope there is someone who helps you as well or it is a bit one way traffic.