To supplement the breast milk with
infant formula, suggest mixing them. Try mixing ¾ breast milk
and ¼
infant formulas at first. If he does accept it, then after a week or so, try doing a bottle mix of ½ breast milk, and ½ formulas. If you wish, you can gradually go to a bottle mix of ¼ breast milk and ¾ formulas, then totally to all formula depending on how he accepts it. When you want to wean him off the breast milk you can follow the above also.