Bones under bones

Hi Forum,
I’ve rigged my character. Under the two leg bones are the leg and the foot object. So far so good.
I want to deform my foot too. So I need bones for my foot. But if I’ve done my bone rig for the foot
it jumps outside my character. What should I do?

Mac, Harmony 15 Advanced

Hey, it’s run with the kinematic output. Great.