Tenant wanting to let a room

My tenant had requested that their cousin rents a room. My tenant had an agreement.
Do I need to give the cousin a tenant agreement or does my tenant have to give them something.
I do not live at the property so they are not my lodger. Is this a sublet?

Write to your tenant confirming that you are happy, if true, for them to sublet, but remind them that they they have full legal and practical responsibility of a landlord over their tenant, their cousin.

You may wish to list those responsibilities, including your continuing right to inspect their room as part of your obligations, and that what ever your decisions are, your tenant cannot assume you have taken over their responsibilities as a landlord to their cousin, and that they remain responsible for paying the rent due to you and any damage that may occur, and taxes on any income they receive from their tenant, if any. They must also allow access for safety checks and emergency access should these be necessary.

You wrote, “My tenant had an agreement.” I assume they still have an agreement, and if the agreed term expired, they still have an agreement, the old one, and it still applies. You can always issue a fresh one if you wish, but that would incur a lot of additional work for you, not just modifying it!

After-thought: if not renting a room, they can stay with your written permission provided over-crowding does not occur, without any of the above. Your tenant remains responsible as per your agreement with them.