There are some patterns in your life that you love from the first sight. Elliedactyl Thatcher (link) is one of them! It is little bit of fancy and at the same time it is still really comfortable and you can wear it to presidential ball or to a sandbox. There are several options but I have only tried one of them. After finishing the ones I have in my list (For a friends son and also for my cousins son) I have my goals set for trying other options too.
You can make it to your NB and also to your 12year old, such a big size variety is one of the things why I love Elliedactyl patterns! The instructions are easy to follow (when you work out that collar part) and it is fairly quick sew after first one.