My oldest was almost 6 when we brought home her baby sister. If you ask her today, she'd still be willing to have us bring Haley (now 7) back to the hospital just so she could be the only child (she's now 13)! We realized that it was a big age difference but my oldest sister & youngest brother are 10 yrs apart & my parents didn't ask our permission to bring him home!!!! Sometimes I think it's hard for our children to express how they are feeling and the one thing that has gotten my oldest to stop in her tracks is when I explain to her that it's normal to feel the way she feels but that she needs to realize that our youngest never had the alone time with us. Haley came into our family w/Sami (our oldest) already a part of things, whereas Sami was our 1st - she was our project, the 1st we did everything with - the one that we learned the most from, and on & on...I think you see where I may be going w/this. When I put things that way to my oldest, she tones down a bit - like when my youngest asks a question while doing her homework and Sami goes to give her a smartypants answer - I just remind her that she didn't come out of me knowing all of the names of the planets, now did she and she gets the hint. I think that a lot of it is that they just don't know how to tell us they miss not being important ones like that anymore because it's almost like they are trying to take on this big role to be this big tough person to this little one they love and care so much about, but can't really show us that because then we'd be onto them and their younger brother/sister would know that they really have a heart! Best of luck to you and know that you're not alone.