premise: Nannina de' Medici (14 February 1448 – 14 May 1493), born Lucrezia de' Medici, was the second daughter of Piero di Cosimo de' Medici and Lucrezia Tornabuoni. She was thus the elder sister of Lorenzo de' Medici. She married Bernardo Rucellai. Her father's name was Piero, so she is sometimes known as Lucrezia di Piero de' Medici.
hypothesis: Lucrezia de' Medici had multiple siblings other than Lorenzo
reason: It implies that she has at least one sibling but we don't know if she has more