Long story short: We bought a bed frame at IKEA in August. We bought a mattress just a few weeks ago. You know, life and stuff. When we went to pick out a mattress, Millie was exhausted and fell asleep on the way to the store. She slept on a Serta (read: we would welcome big advertising money for the adorable model, but were not compensated for this post) the entire time we tested the different mattresses.
If only she napped that well at home! :)