I've just posted a new Instructables. Please find it at: https://www.instructables.com/id/Turn-a-Cardboard-Box-Into-a-Playhouse/
I describe how I turned an old cardboard box into a playhouse for my little girl. Here is a small preview.
"We bought a new car seat for our little girl. It came within a huge cardboard box. The little one loves to play with the box. I decided to turn the box into a playhouse for her and I want to show you how I did it. In this Instructable you can follow all my steps and hopefully be able to build your own.
Please post all your questions and remarks in the comments below. I hope you like it and will enjoy the instructions. Have fun :)"