[3][4] In either case, Juncus is likely not related to the patrician Aemilia gens, although he may be descended from a client or freedman of a member of that family.
Oliver infers that Juncus married Varia Archelais, the daughter of Tiberius Varius Caelianus, the diadochos of a philosophical school at Athens between 107 and 120, prior to his consulship, because "a consular would have presumably contracted a more splendid marriage than that with the daughter of a philosopher.
A letter of Hadrian's to Coronea in 135 shows that he appointed Aemilius Juncus as special commissioner for Achaea, to look into construction works in Boeotia that had been facing ten years of delays.
An inscription attests that, along with the emperor Hadrian, he recommended Tiberius Claudius Hermoneikos son of Pleistoxenos to receive the title of aristopoleiteutes from the city of Sparta.
Oliver makes a persuasive argument that Juncus the older is the author of a philosophical tract Περὶ Γἡρῳς ("On Old Age"), from which an extended extract was preserved in Stobaeus.