At this point, Jo didn't know what the hell to do. She had understood Sam's confusion in the sound that he had made, and Farren's confusion in her sneeze-shake - that headtilt alone couldn't mean anything else - but Farren seemed to have understood what Jo had tried to relay and so her pawing and nipping was met with a series of playful grumble-growls from Jo. Pretty soon she was snapping playfully at her sister, turning to swat at her with both front paws before lowering them and her head to the ground with another playful growl.
If before she made a pleased sound at Farren's gesture toward Sam, a pitiful whine took its place as Farren looked to her for help. She had no idea what the hell to do beyond not attacking Sam even in jest, the scars on her upper body still fresh as anything in her mind. On the other hand, Jo did not want to freeze Farren out either, so just lying there and not playing wasn't an option. Not that she would have minded - in fact, she would not have minded either way; all Jo had banked on for this full moon was taking her mind off of how her brother and sister were missing and wondering in what circumstances they must be having their own full moon.
When in doubt, Jo went goofy and that is exactly what she did in this situation. Laying on her back, she started rolling around, pawing at Farren when she rolled near, and then at Sam when she rolled near him. It was silly, but it was the only thing that occurred to her wolf self. After a little of this Jo rolled back onto her feet and darted off running a while before turning right back around and, keeping the same speed, running right into Farren. She did not want to leave Sam out of anything, but neither did she want to do that to Farren, and she knew exactly how to let Farren know all was right with the world (relatively speaking). The impact sent them rolling again, and to Jo it was kind of like a tackle-hug Farren would not have accepted in human form.