“Beach House Reunion” by Mary Alice Monroe dusts off the venerable ‘cant-go-home-again’ theme, with nieces and grannies and babies on hand to raise sand on the Isle of Palms.  A wildlife sanctuary subplot offers some diversity.  “The High Tide Club” by Mary Kay Andrews tweaks the summer reunion plot by reuniting a gang of retirees.  Their age insures many years of accumulated secrets and resentments to iron out!  Meanwhile, wedding bell blues are ringing in “By Invitation Only” (Dorthea Benton Frank) and “A Nantucket Wedding” (Nancy Thayer), thanks to in-law problems and second thoughts on the impending nuptials.