S.H.
Is he tired?
Does he nap? Oh sorry, he does. Maybe he needs more than 1 nap?
He sounds tired.
I have a boy, he is not whiney.
It is not gender related.
I have a girl too. And SHE was the whiney one.
As an aside: my friend had a baby girl like that. She took her to the Doctor, the Doc examined her closely head to toe. It was found that a blond hair was wrapped around her toe. Tightly... and was getting tighter. It was not easy to see the hair. The Doc removed the hair. Her baby was a different baby after that, and happy. NOT whiney. For her, this was the problem. So... it can be anything. Or just normal developmental 'separation anxiety' or something.
all the best,
Susan