My son is 13 years old and will soon be 14 the law says he is no longer required to use a booster seat in the car. However he continues to use one because he says he just likes it. We have said to him multiple times he can get rid of it but he all ways replies no. I have no idea why he would want to sit on a hard plastic seat that he has had since he was 6. But what i do want to know is, Is this illegal under UK law? should i continue to let him use it or throw the baby seat away and say NO? and if you no longer need one but still use one at what age should you stop using one.