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.
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Five men and a woman died in the crash. A 22-year-old man remains in a serious condition in hospital.