A very similar thing happened in California a few years ago (Santa Barbara, I think). I heard the sister only got reproved and stayed in the hall while the lives of all the others involved (friends, family members) fell apart.
Edit: http://www.edhat.com/site/tidbit.cfm?nid=80905&showcomments=T
Source: City of Goleta Police Department
Detectives have arrested a 41-year old woman from Goleta for having unlawful sex with a teenage boy in 2008.
On Monday, November 11, 2011, a man from Goleta came to the Sheriff's Headquarters to report that his, now adult, son had recently told him about a sexual relationship he had with a woman in her 30's when he was 17-years old.
The following investigation revealed that Lisa Ann Rowell (DOB 8/5/70) and the teenager were engaged in a sexual relationship in the spring of 2008.
Detectives arrested Rowell on Tuesday morning, February 7, 2012 and booked her into the Santa Barbara County Jail for unlawful sexual intercourse with a minor (261.5 PC; 288a(b)(1) PC) on $50,000 bail.
Detectives continue to investigate the case. They encourage anyone who may have information regarding this or any other crime involving Lisa Rowell to contact them at (805) 681-4150 or the Sheriff's Anonymous Tip Line at (805) 681-4171.
Due to the victim's age at the time of the crime, there will be no more details released.