Spoiler :
Novel us unclear about this we can think she is his real daughter at 80% cause her mother died ( if she is ) died before giving birth and was buried with baby still in her....so maybe she is born inside then went out by herself but hum well it's unclear...( sorry maybe I said too much)....
the dragon took her out and gave her to a sub family
And that family is real s*** they throw her away when she was just young but now when they know that she is a dragon they gonna claim their ownership ? What a real trash of bullsh***t . Just try to take her and see our daddy will smash your head and chop it in several piece.
The 1rst who will learn that is the false dad....2nd is her earth family....
What she gonna do next I wanna know and I also wanna hurry. Skip to the chapter that everyone found out that she is his dad real daughter.