Anyone else’s baby start struggling with sleep when they went back to work ?

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I went back to work Monday, and for the past 4 nights he started waking up at 2:00, 3:30, and 5:00, then we’re up for the day at 5:45/6:00. He used to sleep from 9 to 2-3:30am, East, then back down until 6. Please tell me it gets better. I’m so tired.