Car A pulls in to a cul-de-sac while Car B is reversing off a drive for a house to the right. Car A slows to a stop, Car B also stops. Car A then follows the road to the left and pulls up at the far end of the road.
After about 5 minutes the mum of Car B walks over to the passenger of Car A stood outside of the car and says "She has just caused my daughter to have an accident by screeching down the road". She explains that her daughter had to swerve out of the way of Car A and as a result has hit Car C.
Passengers and driver of Car A approach Car B and the driver confirms she had to swerve out of the way. When the driver of Car A explains that she had come to a stop Car B tells her to go away. Car C says she didn't see/know what had happened; she was in the car when it happened.
Who is at fault?