Scottish Law Questions? Ask a Scots Lawyer
I take it the childminder is self employed? That being the case, there is no issue of notice as would normally be required in an employer/employee situation. You agreed a fixed term, then you agreed a one week extension only, therefore there is no question of her being entitled to four weeks' notice. Happy to discuss further if this is not the case. I hope this helps.
If the contract is for review but in actual fact has expired, then I agree with your interpretation. You would have to agree to renew it before it could be reviewed. The renewal was for an agreed period of a week. The were no other changes agreed.