I had this exact situation when my son was first born. We got my dog bravecto (it was the only thing that worked to kill the fleas). After that we washed all clothes in hot water in washing machine and all sheets, blankets, etc. For the carpets we used this and left it on our carpet for an entire weekend before coming home and vacuuming it out. The fleas were gone after doing all of that.
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Good luck and congrats on the new baby!