Lol what is happening

So spoiler
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From other comment that I have read, it seem like the sister went into a different/alternate dimension where the duke and the fl have a kid, some shit happen so she decided to bring the kid back to this timeline, so yes technically the kid is the ml and fl kids but just in a different dimension/timeline.

Imao, really so where's the real niece

The niece never existed, the sister just said that that child is her kid as an excuse, I don’t think she have a kid in any of the timeline. So no niece, the “niece” is the fl kid in an alternate timeline.

I wonder though what is the reason of her sister to keep it for a long time and not telling it, even putting the barrier and not letting the guy knew where they are.

SPOILER.....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................I heard that the sister k*lled the kid in the future. For reasons I don't know. That's why she traveled to another dimension to find their kid & take the baby to that timeline. As for not telling, she probably doesn't like him & just want to mess with him.

Then the sister is the bad one, she has the reason to be mad her.

Bruh
The author sure had some imagination