Probably his daughter, wife and son.

Aeacus is mentioned by Briareos as someone he will team up with instead of Deunan, at Hitomi's birthday party in Ex Machina.

He and Briareos bond over the shooting range. Aeacus mentions that he has a daughter, and that they both have a matching Connexus.

Like Briareos, Aeacus is a cyborg, but only partially converted, with a bionic eye. He has more biological systems intact.

Briareos refers to him by his name at 35m29s in Ex Machina.