Sewing custom-made clothing for him is a perfect way to finally get some clothes that fit! So, in this case I decided to make the pattern in a 5t size with a 6 length.
They fit C perfectly!
I also decided to go for the adjustable waist with button hole elastic. This was a little more complicated, but not by much and is usually quite necessary. Unfortunately, (or fortunately, as the case might be) the pants fit so well that he doesn't seem to need it. It was a good lesson at least.
I used the same grey cord that I did with Ryan's Coastal Cargos which I purchased from Hobby Lobby on a great sale and added just a little contrast with the belt loops - again, the same. I wanted to make then pretty plain so that he can get a little more use out of them since he really needs some pants that fit!