The Post Office should have added interest to the savings too.
www.thisismoney.co.uk/money/saving/article-8369907/How-track-old-bank-accounts-youre-windfall.html
DD had an old BS account from when she was young; it had under £2 in it and they wrote to say they would close the account and the £2 would go to charity but she could reclaim it if she wished.
Little House on the Prairie - Netflix


