According to a tree online, Ellen Maddock's father was William, 1828-1921, the brother of Alfred's mother, Susannah. William married Martha Parsonage in Whitegate on 10th November 1846, and there is a photograph of him.
Re Alfred Watkin Dod, he was with his father in Waterloo, Great Grosby, in 1871.
Although Alfred Dodd had no known link to Liverpool, perhaps that is why he can't be found in 1871?
None of the online trees know where he was at that time.
David