Hi,
Facebook as increased their staff significantly to help police what is posted. We may want not to blame the medium used and focus more on addressing the culture of marrying off children of any gender in any country. That way, we remain focussed on 'children's rights'.
The main offenders in this case are the "sellers" and "buyers" who took part in the auction.
In the end, the extent of regulation will depend on mutistakeholder negotiations on the balance between an open Internet for all and the need to protect privacy, security and human rights online.
Wainaina