Question: Who is Ferdinando D'Aragona Y Guardato, 1St Duke Of Montalto's paternal grandmother?
Sentence (from "Ferdinando d'Aragona y Guardato, 1st Duke of Montalto"): Ferdinando d'Aragona y Guardato, 1st Duke of Montalto (before 1494–1542) was the eldest bastard son of king Ferdinand I of Naples and Diana Guardato, one of his mistresses.
Relevant evidence: Yes