Laodomia, Giovanni's sister, was beheaded because she was guilty of having favored the relationship between Ugo d'Este and Laura Malatesta, called Parisina, the daughter of the lord of Cesena. When Parisina was 14, she married Niccolò III, thirty years older than her. In May 1424 she fell in love with one of his stepchildren, Ugo. Once their relationship was discovered, the two lovers were beheaded on the night of May 21st 1425. The execution method by decapitation, reserved for nobles and important people, is an indication of the high family position acquired by the Romei.
Giovanni had many natural children, all legitimized (Borso in 1457, Lucrezia in 1469, Pietro and Francesco). Sons and grandchildren were used to forge ties, also thanks to marriages, with other important families from Ferrara.
Giovanni's destiny in the ducal court had mixed fortunes: in 1472 he was found guilty of forgery. He was subjected to a fine of 12000 florin. Two years later, he stood as godfather to the daughter of Hercules d’Este and Eleonora d'Aragona, Isabella, future Marchioness of Mantua.