I'm not sure what the mom did to get the dog off of her kid. What ever it was I'm glad it worked. I watched a kennel master pour a full coffee pot of scalding coffee on one to get it off of another dog. That dog let go in a hurry.
Malinois are not known to come off of an attack/bite easily. I've had many of them on a leash and have never been comfortable with them. I'll take a German shepherd or Belgian shepherd over a Malinois any day of the week.
For information, a malinois is a belgian shepherd. There are three belgian varieties, differing only in one being longer haired, one wire haired, the malinois smooth and closer coat.