Nails. She never made any and I did. Duh. Thanks all.

Make some iron nails at your forge

Just if it was not clear enough, to unlock a specific recipe you need to have every subpart in your inventory at least once. For the bed it may be the iron nails or feathers which she did not touch yet maybe the wild pelt too 😁

Dragon bed requires fine wood, deer hide, wolf pelts, feathers, and iron nails.

The Dragon Bed does not come up under furniture? Seems like is is not unlocked for her?

Bosses don't unlock furniture, materials do, as noted above. Well bosses do unlock stuff at the trader... but that's stuff, not recipes.