Re: 3 year old
Not a bad idea, and not crazy, either! A lot of 3 year-olds are still nursing- both my girls nursed until age 3, and we have plenty of mamas here who have nursed longer than that.
The only problem with your idea is the retraining part. Most kids who have been weaned for a significant amount of time don't really know how to get milk out of the breast. They just can't coordinate the necessary movements. It won't hurt to offer, but don't be too surprised if your LO turns you down, or licks you, or just doesn't manage to get any milk. If that's the case, you might want to try pumping or hand-expressing some milk and putting it in a sippy cup, or blending it in with some of her food. Yum!
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"