An incredible theory about Lila's origin. (Nemesis and Season 7 Spoilers)
It has been confirmed that Lila is Tomoe's biological daughter, but there are still unresolved plot holes in this scenario, so it's theory time. Lila's biological father is supreme.
Why did Tomoe abandon Lila and take care of Kagami instead? I believe this is because Lila inherited her character traits from her father supreme who did something that disappointed Tomoe and/or ended up in prison because of it.
My reasoning behind this stems from Supreme's first appearance in the Miraculous Tokyo special. Who else has been to both Tokyo and Paris? Tomoe. Furthermore, we know that Supreme is currently imprisoned. According to my theory, because Tomoe was disappointed in Supreme, she refused to raise Lila herself and instead sent her to Paris with hired stepmothers to take care of her. Otherwise, why would she use a damaged Miraculous to bring a daughter into the world? She wanted a child that fit her own vision of perfection, but Lila resembled her father aka a hardened criminal, both in character and appearance.
Another piece of evidence I have is that the reason behind the light seen at the end of Season 5 remains unknown. In my opinion, that light was Supreme. Having heard either through Tomoe or someone else that his biological daughter Lila had obtained the Butterfly Miraculous, Supreme reached out to her. He granted her the shapeshifting power we see in the Season 6 finale to help her retrieve the Ladybug and Cat Miraculouses (it hasn't been confirmed that Supreme gave her this power, but I don't think there's any other explanation). This is why Lila was so furious in Miraculous London when she failed to secure the Miraculouses: she couldn't break her father out of prison.
