I'm a single Mum, with no real support from daughters father and I'm starting to feel at a loss with her behaviour. She bites regularly during a meltdown, ie I'll take something away from her that she shouldn't have, or move her away from something and she'll have a tantrum and run at me and bite me, or bite my arm (leaving bite marks and bruises). I initially ignored this, but it didn't get better, so thought that saying a firm 'no' would help. But When I'm firm with her she laughs! And then carries on, in fact me being firm seems to escalate her behaviour further. Earlier today she kept wanting to chase my dog, which I obviously don't allow. Each time I'd be firm with her she'd smile/laugh and then she'd chase that much more, or start grabbing at the dog. What do I do if being firm doesn't work? I do often redirect her/distract, but surely she won't learn if I can never set boundaries? I'm starting to worry I've got a terror on my hands