The Snaresbrook Crown Court sentenced Mirjind to 10 years and eight months in jail, half of which he will serve, with the rest on licence. Mirgind, from Ilford in north-east London, was earlier charged with attempt to murder, but prosecutors later accepted a guilty plea to the charge of grievous bodily harm.
He has denied attempting to kill the victim, who was hospitalised for three days after the incident.
The judge told him this was a "manic and horrific" attack motivated by a belief his daughter-in-law had been unfaithful, the report said.
"There is major scarring to her face, there is serious injury to her left wrist, she now has a stutter," the judge said.
"What is so distressing in this case was that your grandchildren, grandchildren aged three and six, witnessed this offence from beginning to end. They pleaded you to stop but you did not stop," the judge said.