Lysimachus was the first-born son and heir of Ptolemy I Epigone by an unnamed Greek aristocratic mother and had a younger brother called Epigonos of Telmessos [REF].
His paternal grandmother was Arsinoe II, a Ptolemaic Greek Macedonian Princess who married his paternal grandmother as his third wife[REF] who later married her full-blooded brother Ptolemy II Philadelphus as her third husband[REF] and through marriage became Queen of the Ptolemaic Kingdom.