Parents, children and jealousy

It is not uncommon to hear stories of fathers who are jealous of their sons or even mothers jealous of the relationship their daughters have with the father. I just cannot help wondering where this jealousy comes from; is it healthy or normal? Can it be prevented with a little consideration perhaps?
Will a mother feel jealous when her husband spends too much time with his daughter?
Will a mother feel jealous when her husband spends too much time with his daughter?
Times Reporter