Three children and a woman were the victims of a horror car crash on the A34 in Berkshire, police say.
Tracey Houghton, 45, of Bedfordshire, died at the scene of the eight-vehicle pile-up together with her sons Ethan, aged 13 and Josh, 11.
Her partner's 11-year-old daughter was also killed.
All four are believed to have been travelling in the same car when they were caught up in the crash on Wednesday evening.
A man was arrested on suspicion of causing death by dangerous driving.
The 30-year-old has been bailed until October 5.
A man who was flown by air ambulance is still being treated in hospital for serious injuries.
A man and teenage boy with minor injuries were taken to the Royal Berkshire Hospital and have since been discharged.
Nine other people who were slightly hurt were treated at the scene following the accident.
The crash took place between Chieveley and East Ilsley at around 5.10 pm, causing major delays and tailbacks.