DS was born 3 weeks ago. DD is 3.5. She had expressed her concerns about his arrival beforehand ("Will you stop loving me when the baby comes?") and we had striven to reassure her. I had, mistakenly, assumed that his arrival would lead to her falling in love with him and, hence, reducing her anxieties. Things have turned out very differently. She had not been prone to tantrums in the past, but these have become increasingly prolonged and intense. She has not displayed much antipathy to the baby (though she tapped his head yesterday). But she is furious with us for all the time and attention we are giving the baby. She hits out at both of us and screams when frustrated over anything, however trivial. We realise that this behaviour is entirely understandable, but that doesn't make it any less difficult to deal with, especially since we are both lacking sleep from looking after the new baby. In the past, we had relied on occasional use of the naughty step and, increasingly, talking things over with her. Neither seems to make any impact. She is highly intelligent and responds to attempts on our part to reassure her ("DS will need less of our time when he is feeding on solids and needs to spent less time eating") to escalate her antagonism ("So I'll keep crying until he stops drinking milk"). I feel we need to go back to the drawing board in dealing with her, but feel like I've lost the map. ANY suggestions would be helpful. Thanks!