I think bathing suit bags for post-pool/beach are essential. I always travel with mine and take it with me to the pool when I go with H. I can just throw the bathing suit bag into my tote or the diaper bag and I don't have to worry about anything getting wet. On my most recent beach trip we went to the pool right before we left for the airport. I didn't have to worry about everything else in my suitcase getting wet. My current one is from Gap (years ago) but I think I might get a new one (the colors are faded).
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