The one year old girl was injured along with her mother in a crash between the car they were in and an HGV at the junction of the A49 and the A456 in Woofferton, which is just inside Shropshire.
Three ambulances and a rapid response vehicle were sent to the scene after the crash which happened at about 7.40pm on Wednesday evening.
A West Midlands Ambulance Service spokesman said: “When crews arrived, they found a car that had very significant front end damage. The lorry had side damage.
“The child had suffered a serious head injury. After stabilising her condition, she was taken on blue lights to Hereford County Hospital where medics were on standby for her arrival.
“Her mother, who was estimated to be in her 20s, was taken to the same hospital with a wrist injury and pain in her chest and neck. Both were immobilised before being transported.
â€The little girl was later transferred to Birmingham Children’s Hospital by their paediatric retrieval team.â€
Police have appealed for witnesses to the crash which involved a red Vauxhall Astra and a heavy goods vehicle.
Police Constable Colin Martin, who is investigating the circumstances of the crash, appealed for anyone who may have seen what happened to contact police on 0300 333 3000.
“The HGV is believed to have been travelling southbound on the A49 and the car in the opposite direction when the collision happened, at the junction by The Salwey Arms pub,†he said.
“Anyone who may have witnessed the impact itself or the manner of driving by either vehicle involved immediately beforehand is asked to contact police on 0300 333 3000.â€
The road was closed until about 2.30am today while police collision investigators worked and the vehicles recovered.