"NOCHE DE SUENOS"
Jo Lupo, head of security at Global Dynamics in the town of Eureka, Oregon, said she grew up with no mother and three brothers. This would mean her mother died or left when she was young.
One of those brothers could be Cyrus Lupo, now a detective at the 27th Precinct in New York City.
Near the beginning of this final season of 'Eureka', Jo visited her old family home while on her "walkabout". Because she got back to Eureka fairly quickly after that, I have to assume that she was still in Oregon, maybe in Washington state. So Detective Lupo must have moved to New York City after high school or college. (He went to a Catholic school earlier back in the Pacific Northwest, and is now attending law school at Brooklyn College.)
Like his sister, Cyrus Lupo served overseas - Jo was with the US Army Rangers, while he was working with the NYPD Intelligence Division investigating terrorist cells in the Mideast.
Jo may have had an identical half-sister by the name of Bowers in Seattle, Washington, (as seen in 'Dead Like Me'). This would suggest each of them had a parent who was fooling around......