Bwah, I think its rubbish too. I am the middle child and can honestly say that I don't feel hard done by, mistreated or ignored. I was the most academic, had friends at school and generally got through my teenage years without a drama (of course I was a total ***** to my mother as I entered puberty but that's definitely not a middle child symptom )

I think that some of the issues that children carry into parenthood are certainly due to poor parenting, unfortunately there are lots of dud parents out there. I think that considering this is something you are thoughtful about, your DD2 and #3 will have nothing to worry about as you as a Mum have all bases covered to ensure your children are treated equally but uniquely.