DD1 20m, DD2 4m. Never had any problems with them together before beyond what you'd expect - ie DD1 doesn't really "get" being gentle. But never any maliciousness.
The last few days she's start biting, mainly me but now a couple of times DD2. Shes overtired due to the clock change, and maybe is going down with something. But this is quite weird. The biting doesn't seem to be coming from anger - she'll be playing and cuddling one minute and the next will go in for a chomp!
Have explained at length that teeth are for food, and biting hurts people. DD2's screaming when DD1 bit her definitely upset her. But dont know what to do beyond that.
Any ideas v gratefully appreciated.