Thank you so much for replying
I understand what you are saying about 'Alpha dog' but it seems a little strange to me.....Kaddie wasn't alpha dog...if anything, Twinkle was 'in charge' of Kaddie and Wicket, but she has never before tried to be boss of me, my husband or children. But I totally agree that maybe she feels confused where she fits in now that one of the pack is gone.
I too feel it is behavioural rather than medical...I've made a vet appt anyway, just to be sure, and maybe they have some advice for me too. I'm going 'back to basics' with her training-wise and am considering consulting with and possibly hiring a trainer. It's very disheartening because her manners and behaiour have always been fantastic, but I'm willing to put the effort in.
Thank you xxx