I'm struggling with the difference in rules between ce que / que and ce qui / qui. Is it correctly understood that we use either "ce que" or "qui" when followed by an object (so the rule is different with/without the ce, unlike with verbs and reflexive pronounse)? Are these two sentences correct, "sa maman" being an object here?
Tu ne devineras jamais ce qui sa maman a fait!
Le bébé joue avec la peluche que sa maman adore.