I’m The Only Granddaughter Of The Strongest Duke

Lord, please allow me to sabotage his business again today.
That’s how my dad will not die.
***
A weaponsmith who lost his life while crafting weapons for the warrior’s party.
That foolish man was my father.
Upon realizing the future, I took drastic measures in order to save my dad’s life.
That was through sabotaging his business!
“Darn it, why is such a cool sword can’t even cut this tiny potato-!”
“It can’t even slice the ham this time!”
“There’s no way that the sword made by ‘Sir Royce’ would be this useless-!”
My trick to sabotage his business was successful.
But I didn’t stop here.
I spoke courteously to the warriors who came for my father.
“Nial Royce? I don’t know that person. I only live with my mom.”
Sorry, father.
***
My plan was a huge success.
Only flies flew to my father’s weapon store, and the warriors didn’t come to ask for a sword from my father.
I thought I could live happily with my father now…
“You….How old are you this year, child?”
The most powerful duke of the empire suddenly claimed that I was his granddaughter.
What the hell is going on here?
What is happening with me?