I think it was mean and irresponsible as a parent to talk down on one daughter to the other... but life can sometimes bring disappointments even if you feel its unfair because he is your dad and he should support you.. just let his words be motivation to follow your dream good luck :).
If you were considered good by your coach when you did gymnastics and you think you are good then you probably are. My mom makes fun of me for my music but I have had professionals tell me I'm good so I don't let it get me down. He could have just been trying to make a mean joke don't let it get to your head, parents are supposed to be supportive but that doesn't mean that they aren't also going to make fun of your dreams sometimes.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.