I've been sewing pants for N to wear this winter, and I think I've got all the kinks ironed now- though she grew out of them the day after I finished them- so I had to add some panels to the fronts of them. I started with this tutorial, and then made some changes as I went- adding a contrasting waistband,
initially because I made them too short waisted, but then because I liked the look of it. And then I added the flat panels in front (which also have a pleat in them, so that I can unpick it when she grows and they'll last a little longer), because she literally grew out of all three pairs of pants overnight.
They're very slim through the hips which is perfect for her non diapered bum, and they're reversible, with Flannel on one side and cotton on the other, which makes them super super cozy, and easy to bum around the house in. The unforeseen bonus of lining child's pants with flannel is that the pants will also sop up most of the accidents that happen while you potty train said child. In fact they're so absorbent that the pee doesn't even get a chance to hit the ground! (my amazement here proves an unspoken rule- never eat anything off the ground of a house that has potty training kids in it. never. ever.)