[maggief]

Half siblings.

http://www.effinghamherald.net/section/10/article/28262/

An Effingham County woman and her half-brother were arrested Tuesday on charges related to them having sex in a church parking lot in the man’s truck.

[johniegrad]

Thanks. The reason they knew it was an Effingham County woman and her half-brother (and not the reverse) was because he weighed half as much as she did ;-)

Joking aside, no way this is new behavior. They've just never been caught before.