This is my first time trying to breastfeed but my bby won't take the boobs so I been pumping but he seem to still be hungry all da time so I started giving him formula 2 ounces rite after giving him 4 ounces of breast milk so anyways my ? Is can I mix half breast an formula together without him getting a upset tummy. I really dnt no how to get him full so he can sleep and mke it easier on me am I wrong for that...