How can I tell Unity's parenting system: "For this frame, don't make this parent's translations affect its children's transforms"?

I'm making my own physically-moving-rag-doll-kinda character, and I want his one (so far) foot to move freely yet receive all of the pelvis's (the parent) translations, but sometimes I want the foot to be still (when he's making a run-step forward, adding impulse to himself). If I could tell Unity that I don't want a parent not to affect a child for a specific frame (in this case all the frames in which he's making the stride), it would be nice. I know I can make it with code, by making the foot receive all of the pelvis's translations When I want it, or, if I parent them, by making the foot have a fixedPosition vector and use it when needed to cancel the parent's movement When I want it, so there's no need to show me solution examples, I was just wondering if I can use something Unity has and I'm not aware of.

Just set position, rotation directly:


as separate from:


The local ones take into account parent transforms, the normal ones are relative to worldspace.