My sister is in her early 20s and it's become apparent, at a series of family occasions and meet-ups over the past year, that she is very very jealous of DS, her 11 month nephew. Specifically jealous of how my parents have just loved him since birth, are really keen to spend time with him, talk about him all the time. She was the baby of the family before, but I would have thought at her age this is a bit silly. Its become a real issue - when I was pregnant she kept saying she was "bored of the baby chat", she stormed out in tears from our last Sunday lunch at a restaurant and prior to that, the last family gathering at home at Easter, was crying and tantruming all weekend. At first I was inclined to think it a bit funny, and I thought it would pass. But now its getting a bit serious and I really don't know what to do. I want to shake her and tell her she's being ridicuous and that she is our parents child, and a grandchild will never take her place, but please to enjoy her nephew...