My baby is 3 weeks and 3 days old, we have been breastfeeding only but it was getting to much and she wasn't happy or settling so as of yesterday we moved to formula, sma comfort 4oz each bottle every 3/4hrs approx. longer at night. However i am still expressing as hope to mix breast milk expressed and formula but what's the best way to go about it? Today she has had one 4oz formula bottle first thing, and 2oz of expressed milk this morning which she seems satisfied with. I have made a formula bottle in case the expressed wasn't enough - so far she hasn't requested it