Aamer Araf carried out the “brutal attack” in May last year after suffering from paranoid schizophrenia, a court heard.
The 33-year-old, of Oldbury, pleaded guilty to wounding with intent and to causing grievous bodily harm with intent at an earlier hearing.
Wolverhampton Crown Court was told the victim was left with a “significant wound” to the top of her cheek, just below her left eye.
She had suffered a wound to her breast and three wounds to her left buttock along with wounds to her arms and wrists.
The seven-month-old had suffered a left-sided skull fracture along with bleeding around the brain and within the brain tissue.
Araf had been suffering from paranoid schizophrenia and was Tasered by police during his arrest.
Judge Michael Chambers QC was told the defendant had expressed the remorse and “but for his illness, this offence would not have occurred”.
Sentencing, the judge described the incident as a “sustained and brutal attack” and said it was “quite astonishing” both victims had made a good recovery.
Araf, 33, of St James Road, Oldbury, was sentenced to eight years in prison for the offences to run concurrently, with the defendant subject to a licence period of four years.
Not guilty pleas were entered on the defendant’s behalf to charges of two counts of attempted murder against the same people.