My guess is that the council will have families on a waiting list who have priority claim on the house if the legal tenants have moved out. The daughter (who I assume is single) would not qualify for a family sized house unless Scotland council housing rules are different to the rest of the UK, especially as she has lived there for less than a year (might be different if she had always lived there with her parents but still unlikely). I knew a guy who lived in a council house with his mum and had to move out when she died. He got a council flat because he was unemployed otherwise he would have had to find his own home. She will probably have to declare herself homeless when the council tells her they intend to move in a family that needs the house and hope they will offer her a flat, that's if she qualifies for social housing. I'd be very surprised if she's allowed to stay.