We stayed in the most darling hotel in Heidelberg - Hotel Hirschgasse. So cute it is worthy of it's own post. The room we stayed in truly was a 4 year old's delight. Eva immediately went into character - princess character. She called herself Princess Rosa. Being a princess in our room mostly required sleeping in the princess bed. It was indeed a bed fit for a princess. The only snafu came when Bryce and I were ready to head out and walk to Old Town. She said she just wanted to stay in the hotel room and play. Groan. So, I gave her the "you can't see the world from your hotel room lecture" and we headed out.
Just in case you ever stay there here are a few tips. If you have more than 1 kid, request a "family" suite. Booking.com does not give you that suite option, but 2 of these rooms exist at the hotel. Skip the hotel breakfast. It was expensive and really nothing special. Go into town for waffles instead. We reserved our room through Booking.com, which gave us a much better rate.