Whenever possible, I like to work with doll supplies on hand, rather than buying new. Therefore, since I wanted to make a Little Bill with the recently released adorable Mattel Skipper Babysitter Inc. AA doll, I used an articulated body that I already had from Mattel Made to Move Gabby Douglas. I yoinked the Babysitter head off the original body and spent several days hacking the MTM body to the appropriate size.
I am never modding an MTM again. Unlike a Spin Master Liv body, which has partly [but not fully] solid limbs and a hollow torso, the MTM body has solid limbs and nearly solid torso pieces. That’s a lot of plastic to cut through.
Furthermore, the proportions of the MTM don’t lend themselves to creating kid bodies. While the Liv’s limbs are largely tubular, thus shortening without much deformation, the MTM’s limbs are just weirdly shaped throughout. The MTM’s elongated ankles are the worst. I cut down the core and limbs until the proportions looked good, then gave up on the ankles. I took out the feet and jammed the stumps into shoes that I filled with Aves Apoxie Sculpt. Covered by clothes, the reduced MTM looks convincingly like a chubby kid.