Put the condition beside the option it controls
Write the plan in a sentence: “Book the Friday departure only if Kim agrees by Tuesday morning to watch the dog through Sunday evening.” Ask Kim about the actual hours, responsibilities, and any limits on their availability. A past offer to help with the dog is not confirmation for this trip. Check the provider’s current booking and cancellation terms to establish how long you can wait without committing money or losing the option.
Choose the alternative before the deadline
Prepare the alternative while waiting. If care is unavailable, would you change the date, take the dog, or skip the trip? Agreeing on that answer in advance keeps a late reply from turning into pressure on the relative or a rushed purchase.
Act on the answer you actually receive
If Kim can help on Saturday but not Friday, the original condition has not been met. Consider the alternative you agreed, such as moving the departure, arranging different care, or staying home. Confirm any new arrangement with the person who would provide it before booking. If no answer arrives, let the hold expire or release it as its terms require. A deadline creates a need for a choice; it does not turn silence into a promise.