Closely associated and children are not same. People work closely in profession that is not same as being a family. You work with your female boss in office that doesnt mean that she is your family member. Understand that.
Periyar and Annadurai were close, but that dint mean they had sexual relation right?
Of course Karuna is close to Ki Veeramani of DMk and they may be having a "physical" tie, but that doesnt mean every body is like that. dont try to generalise things right..