On of my Plan B's is to develop my Baby Clamp, designed to prevent 'twisted nappy syndrome' where the little sod spins round just as you attach the second and decisive fastener. A simple metal frame with hand and feet restraints. Kid gets up and wanders off with a wonky nappy but not with Stek's Patent Baby Clamp.
My ex-colleague developed a fool proof method of combatting toddler child-seat body-arcing, where the little swine refuses to sit in the seat properly, arches it's body right out making it impossible to buckle-up the restraints. Discovered by accident initially, you basically crack the kids head on the car door frame as you put him/her into the carseat, kid doubles up in pain and fits the seat perfectly, buckle up quickly before kid realises it's been duped.