I'm going to be honest and say this is one of the few threads I won't be donating in. Although it's a nice thought to help your friend I think this would be a lesson best learn't herself. She should be the one earning back that kiki slowly as she is the one who broke a rule on gaia.
It appears to me she has too options:
~As she sold the kiki she should have the worth on her account to pay it back very easily.
~If she blew it all on the emerald seeds(or similiar) she should get her sister to report her for scamming:
http://www.gaiaonline.com/gaia/report.php?r=2As she has sold all her possessions with the intent on giving them to the sister she won't have much of the account left anyway. It also shows she is willing to take responsibility for the action itself.
Gaia will attempt to return the item after investigation. Depending on how quickly you earn gold-it will probably be quicker.
Sharky-Item Quests Team Leader