I, too, am interested in the early Seabrooks of Buckinghamshire. I have only a very early Seabrook in my line, Mary Seabrook born in 1601, daughter of Robert Seabrook and Alice Goodspeed. Could this be the Robert Seabrook at the top of your line? Mary became (ca. 1634) the second wife of William Preston. William hailed from Chesham, County Bucks. He and Mary and a number of their children emigrated to New England aboard the ship True Love in 1635. Mary died some time after 1680 in Stratford, Conn.
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