Nailit, I don't know why you are ignoring the fact that the bailiffs have to prove your son lives at your house before they can take anything. I conclude that ,actually, he is in some way connected legally to your home so you are now worried you have no proof he does not own anything in your home. Bailiffs and Collectors will take goods from properties when and only when they HAVE PROOF of residency and YOU have no proof the goods belong to you.
You might take note I worked at Marstons in admin a few years ago -look the name up.....