Idiom
keep someone or something still and hold someone or something still
Theme: RESTRAINT
to restrain or control someone or something so that the person or thing cannot move.Please keep your foot still. It makes me nervous when you wiggle it.You have to hold the nail still if you want to hit it.
Idiom
keep still and hold still
Theme: MOVEMENT
do not move.Quit wiggling. Keep still!"Hold still. I can't examine your ear if you're moving," said the doctor.