[Buster Brown]

Hi and welcome to Yorkie Talk. Sometimes when they are taken from their Mom's at too early of and age they do not learn proper doggie manners. When she bites try crying out in pain with an ouch and disengaging from play so she knows she hurt you and that when she does that she loses her playmate. I think that pulling on the hair would be seen as playing and you biting back with your hands so that reinforces play biting. Time outs in the cage help break the pattern but I would worry that you make the cage less of a home and more of a punishment so they may come to not like going in their cage as it is the "punishment room" It is a fine line training and not breaking their sweet feisty spirits. Hopefully others will add their advice.