Anyone know the title of this book?

My friend was trying to describe a book that she has read a couple of years ago set during the Ripper murders, its about a young girl (around 17) who is having money troubles and turns to prostitution at the time of the murders, she has no parents and has a younger sibling (she can't remember if it was a brother or sister). The girl starts to become suspicious of a neighbour or family friend who is a doctor. That's all she can really remember of the plotline, it wasn't a newly published book when she got it as she got it from a charity shop and she said the cover was fairly old fashioned and the book was well worn. If anyone can work out what book this is from the few clues given we would be gratefull, thnaks :)