Name this book challenge

[Auntlinny]

So, can anyone help me ...

A book I read as a young teen pinched from my grandparent's bookshelf and so probably not appropriate and a bit trashy. Set in London, probably the east end over a long time period in first half of 20th century. Lots of families in different houses on a terraced street. Strange identical twins living in one of the houses. Sinister behaviour. Called Peter and Paul I think. And that's all I can remember.

[BoiledEggonLegs]

Anything to do with the Kray twins? Or set earlier than that?

[Auntlinny]

No, not the Krays. Earlier I think,but over a long period of time and lots of families coming and going. Years old.

[DuchessofMalfi]

Is it London Belongs To Me by any chance?

[bebumba]

The Empty Sleeve by Leon Garfield?