The man arrested on suspicion of dangerous driving and bailed pending further investigation is from Solihull, Staffordshire Police said.
Police are appealing for witnesses to the crash.
A detailed investigation of the scene was done by police and the vehicles involved will be thoroughly examined later as the investigation carries on, a police spokesman said.
He also said that specially trained family liaison officers are supporting the baby's next of kin.
More top news
More than 1,000 children have now used the service at County Hospital since it opened twelve weeks ago.
The Lincolnshire Sustainability Transformation Plan (STP) has been released in full today, after it was leaked on Monday.
If you think you, or a friend, may be suffering from postnatal depression we've created a guide designed to explain and help.