[overly long explanation]
 
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Twilight: The fact is, I’m a princess now. I’m sovereign to local region and to an ideathe ideal of friendship. I have royal responsibilities to my subjects–they are, perhaps, my children. Can I afford to have a biological child? Would that not take my attention away from my people? Can I can risk that responsibility for a selfish desire?
 
Long ago, early in their reign, Celestia and Luna took mates and produced children… it was a difficult time for them, and they do not recommend it me.
 
But even if I decided to try it anyway–I know that right now is definitely a bad time.
 
Rainbow: I can keep telling her I can handle it! Sure, I know I’m still trying to get into the Wonderbolts, and running my own Junior League Flyers team–but I still can make time for a kid. I gotta have someone to take on my legacy and teach all my best tricks to, you know?
 
Twilight: What about Scootaloo? Did you still want to consider adopting her?
 
Rainbow: Maybe yeah–Scoots is awesome and all. But it would just be a paperwork thing. She’s already almost an adult herself. I missed a good chunk of her childhood. She really is more like a kid-sister to me than anything else…