When my second baby was born I used the Organic Fitted on him starting when he was 3 days old. For the first 2 weeks I did the newborn fold and didn't use an insert at all. Then I started using the BabyKicks Doubler because it is a little shorter than the small JoeyBunz with the same absorbency, and the perfect size for "fresh" babies. Now that mini #2 is 3 months old & (guessing) 13lbs I alternate the small joeybunz and doublers. This just because I have them, I could very well use a medium. I do use medium JoeyBunz on mini #1 who is 16 months and 24lbs (again, a guess)

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