In some ways yes I see that there can be a middle child syndrome, but not necessarily by the parents. And yes this was one of the reasons I really wanted to have 4 children.

My eldest son is absolutely doted on by his paternal grandparents, has had lots of sleepovers (there request) surprise little presents every now and then.

I had my 2nd son and honestly it was like he never exsisted in there eye, I don't think they had a picture of him put up in there house for over 2 years, they rarely choose to spend time with him and it was quite obvious (even to him eventually) that he was left out. I then had my 3rd son and my in laws think he is just gorgeous and now gets the same attention my eldest did.

I now find that I'm compensating for them, I'm overly conscious at times of the difference so try to give him that bit more. That being said he has a less demanding personality than the other 2, he is happy with his own company and isn't constantly at you wanting attention (will probably stand him in good steed for later life).

Have just had my 4th son, so don't know his personality yet but I am aware that I don't want him to grow up the spoilt little baby like my BIL is.

(Bit concerned to hear the 3rd child in a family of 4 is trouble....think my nearly 3 year old is living up to that reputation at this point in time)