Re: can milk dry up if still feeding?
If your LO is still nursing effectively, he will maintain some level of milk supply. But older toddlers, preschoolers, and children often become sloppy latchers and indifferent nursers, and that can lead to diminished supply. I'd say that explains what you're experiencing, though I'd also consider the possibility of pregnancy, since that would both decrease supply and explain breast tenderness.
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