Hi, the sleeping pattern of a baby changes throughout their growing up stage. Is there any changes to the environment or increase of noise to the surrounding? Unlikely due to changing of milk if its the milk likely chance of loose stools. Baby might feel insecure thus keep waking up. U can assure baby by talking to baby to let them know u r just beside them. Both my kids still wake up in the mid of the night. Then I will tell them to lie down and sleep once they heard my voice they will stop crying and go back to sleep. Hope it helps.
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