First things first. You all know I love Lysandre. Greatest criminal mastermind of all time, 10/10. Anything that has to do with him? I'm interested. So be warned if you do not want to see more Team Flare fangirlism. 

So, so so! I was talking to an NPC outside of Aether Paradise, like just outside of the Paradise. He says this: 

"The current president's father was a very wealthy man, and a great lover of Pokémon. He built Aether Paradise to protect them." 

So, let's list the facts about Lusamine and her supposed father. 

Lusamine: 

-pretty much insane

-very concerned with beauty

-loves Pokémon 

Her father:

-loves Pokémon 

-very wealthy

Who is wealthy, and loves Pokémon? I think we all figured this out by now. Good (bad?) old Lys! We all know that right after you beat the Anistar Gym, Lys goes pretty much insane and shows his true colors. But at the same time, even though his plan for a beautiful world was to be underway, he felt for the Pokémon that were to be destroyed. 

And Lusamine.. If she were raised by Lysandre, she would have grown up with these beliefs. So if these beliefs were imposed on her, they would have stuck with her for some time. And now, when she is over 40 years old, she wants to create a new world full of beauty, otherwise known as Ultra Beasts. She went pretty much insane as well. But since nobody just goes insane for no reason, the insanity may have something to do with how she was raised. And growing up with a father like him, it would've been entirely possible that he was the reason for her insanity. 

And look at Tem, blabbering on and on. This probably makes no sense whatsoever! 

Now in conclusion, due to the uncanny resemblance between the two, I believe that Lysandre may be a secret part of the Aether family. You cannot sway me from this belief, so please do not try! Thank you for reading, and I may be posting some fan art of those two! Maybe... I'm still coming up with ideas. ^-^