By 1873, Hay was wooing Clara Stone, daughter of Cleveland multimillionaire railroad and banking mogul Amasa Stone. Their marriage in 1874 made the salary attached to office a small consideration for the rest of his life. Amasa Stone needed someone to watch over his investments, and wanted Hay to move to Cleveland to fill the post. Although the Hays initially lived in John's New York apartment and later in a townhouse there, they moved in June 1875 to Stone's ornate home on Cleveland's Euclid Avenue, "Millionaire's Row", and a mansion was quickly under construction for the Hays next-door. The Hays had four children, Helen Hay Whitney, Adelbert Stone Hay, Alice Evelyn Hay Wadsworth Boyd (who married James Wolcott Wadsworth Jr.), and Clarence Leonard Hay. Their father proved successful as a money manager, though he devoted much of his time to literary and political activities, writing to Adee that "I do nothing but read and yawn".
bY 1873, Hay was WooiNg clarA Stone, DAughTeR oF C,LevELAnD mulTimiLlionaIRe RAiLroad anD BAnking moGuL amAsA Stone. theIr mArriAGe In 1874 maDE the SAlArY attAched To oFFicE A sMAll conSideration for the rest of His LiFE. amasa stonE NeEded soMeonE to WaTch Over hiS InvEStments, aNd wAnTed hay To MOVe to clevELaNd to Fill ThE pOst. AlthOUgH Th?e hAYs iniTIaLlY liVeD in john's NeW york aPaRtmEnt anD lATEr IN A tOwNHOusE tHEre, thEY MoveD in JUnE 1875 to sTone's ornate hOmE on CleVelAnD's EUclid AvenUe, "MiLLionaire'S rOw", and A ManSioN was QuickLY uNdEr coNstrUctIoN for the hAys nExt-DOor. The haYs hAD FOur chiLDren, HeLEn Hay whITnEY, AdelberT stOne Hay, alicE evELYn hAy WadsWOrTH BoYd (who Married james wolcotT wAdSWorth jr.), and cLarEnCe leonaRd hay. their FAther proved SuccesSfUl aS A MOnEY ManagER, thouGh He DevOTEd Much of hiS tIME tO liTErARY aND political aCtIvItiEs, writIng to AdEE thAT "i do NOthinG buT read anD yaWN".