When is our vacation?

So this summer we have renteda house on the beach in Dewey and the whole family is going down. It is going to be great. But we really dont know when it starts. THis is an issue beacuse my sister is getting married and she called to ask when our vacation sttarted so she could pick a date. I asked Newell and he radomly tells me it starts Aug 11th. So Kelly picks the date Aug 4th. Just last week, Newell was invited to play gold and he tells me he cant go because the trip starts on the 4th and that is when we leave for vacation. I say no honey remember you toldmet he 11th and my sister is getting married on the 4th. SO. here we are now going to my sisters wedding and recxeption with all of our stuff in the car and than down to the beach. We lose a day and will have to shop and upack on Sunday all becausse Newell just wouldnt double check the dates. UGH...