Way back in the beginning and middle of Season 1, Vince and Dave at first seemed like 2 old lovable brothers and newspaper reporters who held many secrets.
Now by the middle and end of Season 3, it is revealed that they secretly own 1/2 of the property of Haven, that they have a love & hate relationship, that Vince is the top boss behind "The Guard", (not even Jordan knew that part, the whole truth) and it shows his tattoo appearing and disappearing.
I had always thought they had a curse as well that would be revealed by Season 2 or 3, but it hasn't. But, as top boss with the tattoo, it only appears on the troubled so now it is definite that they have one as well. I often thought since the beginning of Season 3, Duke should test their blood, especially during the "Who is the Skinwalker?" episode with all the main characters gathered together.
Since we finally see them as around 20ish & 22ish in 1955 and they are with Sarah at the barn, attempting to blow it up, that means they would be 47ish and 49 when Lucy arrives in 1983, and about 74 and 76 when Audrey arrives in 2009.
But how long did each reincarnation of Sarah/Lucy/Audrey actually stay around for? I noticed on the missing persons report, James Cogan was born August 1956 so Sarah was around at least 1 year to possibly 1 1/2 years. Audrey arrived in 2009, but is it 2012 in the show or is she only there 1 to 1 and 1/2 years now?