The book never says.
Fred, in all of his conversations with anyone, never mentions his parents, only that he is the nephew of Ebenezer.
The only information we get is in the conversation between Ghost of Christmas Past and Scrooge, talking about Ebenezer's sister, Fan:
"Always a delicate creature, whom a breath might have withered. But she had a large heart. ... She died a woman ... and had, as I think, children"
"One child."
"True. Your nephew."
"Yes."
Fred
It is correct if you are talking about more than one nephew. If only one nephew is involved, it is nephew's father. My nephew's father is my brother. I am talking about one specific nephew. If you mean to refer to the father of your nephews, then it would be nephews' father.
nephews!
Your father's great nephew is the son of your father's niece or nephew. Your father's nieces and nephews are your first cousins. Their children are your father's great nieces and great nephews, and are your first cousins, once removed.
Your father's nephews and nieces are your first cousins.
No Scrooge has no children. Bob is Robert Cratchit and is Scrooges Clerk
I have three nephews.
The plural of nephew is nephews.
She is never named in the original book as she is not a niece but Scrooges nephews wife
Nephews is a plural noun.
Nephews and/or Nieces
Nieces and nephews are the children of your siblings.