Well, you definitely can't make a great temperament assessment on a dog when it's first brought home, a lot of times their personality doesn't come out really for a week or so. They're nervous and shy at first, sometimes. I would just carry a toy or chewy or something when you're going on walks. Buy a little treat bag or carry small tidbits of treats (I give Finn cheerios, cuz they're cheap and don't ruin his appetite) so that you can train her on leash and train her to behave. I wouldn't let the kids walk her until she's trained on the leash, to begin with. But, if you keep a clicker and treats, you can keep her distracted, and, looking up instead of down at ankles. You may want to train her on leash, without the kids around at first. In a location with fewer distractions. Does she nip any other time or just when they're walking her?