He should encourage to feed, but should never be forced, as this creates an aversion
Give small quantity of food, gradually increased as per demand.
If he rejects any food item, it should be stopped, and may be reintroduce a week or two later.
It is preferable to introduce only one new food a week, so that intolerance can be spotted.
NOTE: Sometimes its very difficult to accept new food, so at time try one type of food for several days.
I would asvice:
Encourage for Confidence in your baby
Careful attemtion to your baby.
Watch for his weight (whethere it is normal to his age)
You should get her evaluated once for her complaint to get her examined physically by a pediatrician
"i wish your child good health"