Is your baby spitting up or vomiting? If she is spitting up then is reflux which is very common. You can minimise spitting by burping your baby several times during each feeding, keeping your baby in an upright position for 30mins after feeding and make sure the diaper is not too tight that it puts pressure on the baby's stomach. If she is vomiting milk, then you may want to bring her to see a PD.
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