I, The Knot Dr, had the same issues with my daughters: they would look at the hairbrush with fear and associate it with pain. Brushing was not a good experience!
The quality of the brush makes all the difference, as well as patience and careful/consistent brushing. You need be vigilant and keep brushing every morning and at night. Brush the hair against the head and do not lift the hair as this will tend to pull more. When in the shower or bath be sure to use this time to thoroughly detangle the hair with conditioner and a Knot Dr Pro or Pro Mini brush. Be sure to have the water flow from the top of the head downwards.
I also usually divide the head into smaller sections and always start at the base of the head and work my way up and also the ends of the hair of each section and work my way up.
If the hair is starting to develop a 'dread like’ appearance, start at the base of the dread/knot and brush out slowly and gently to remove. Repeat this procedure for any other knots. The first time will take the longest but constant attention to grooming will eliminate the reappearance of these annoying knots.
This is where engaging the child into the process can make it easier and why I purposefully designed The Knot Dr.’s Knotty Kids® for children. Knotty Kids® fits perfectly in their little hands, but the Flexalite™ bristles are just like the full-size brushes. It helps them take care of their hair just like the grown-ups.