Hopefully you can find an experienced solicitor who can quote you a modest sum to do this. As it's with a relative it really shouldn't be too onerous, you would think.
The only complexities would be if you have a mortgage or other loan secured against the property or might want to get one.
If you think there could be a circumstance in which that charge had to be enforced, (for instance if you became insolvent, or died, or there was a divorce, or a lender foreclosed on a loan, or some other creditor came after your assets) then I would definitely think a solicitor should have been involved in order to ensure that your relative is at the head of the queue. And I would tell the solicitor what circumstances you particularly want protection for.