Second cousins and marriage

If one's parent's are second cousins themselves and that one wants to marry his second cousin is there any possiblility that his children might not turn out normal or might suffer from any problems.  Here is the relationship.  

What if for example:

My mother and my father:  My mother's father and my dad's mother (their father's were brothers)

Now the girl I want to marry:  her father and my father are cousins from my father's side. My grandfather and her grandmother are real brother and sister.

This isn't my story but someone else's who doesn't really speak English but I would like to find out for this person if possible.

[Jaybay]

The way I understand the law is that 1st cousins cannot marry.  That law was established for fears of problems to any children from such a union.  Second cousins may marry, but you would have to check the laws in the specific area you plan to marry.  

[sammijo]

I just found out in the states of Alabama and Tennessee it is lawful (yes you can marry) your first cousin and this person is even though they are being rejected by all their families... I am not saying a word...I am not married to my cousin.... hehehe
sam