Do you think that Twilight Sparkle and Shining armor's brother in law is Blue Blood now. Since I kinda believe it.
I think this is because Princess Celestia has a nephew and a niece. Her nephew is Blue Blood. And her niece is Princess Cadence. And since Shining armor *clears throat* I mean Prince Shining Armor married Princess Cadence and Twilight is Shining Armor's sister. So Blue Blood's brother in law would be Shining Armor and his sister in law would be Twilight Sparkle.
Do you believe it? Do you think my explanation is reasonable? And do you have an explanation about how I may be wrong or how I'm right?