This is the flannel fabric I bought to make pajama pants for my grandson Rowan. I used several tutorials to see how to make my own pattern and sew them up. Here’s one I liked at Instructables.
I used these bottoms in a size 2T to draft a pattern on parchment paper. I used 1″ pajama elastic at the top. They turned out really cute. Will add a photo later of his new pirate monkey PJs. He loves them.