There is no reason to think that being a later-born identical twin resulting from cloning would change the overall assessment of being a twin. There is no rational basis for the idea that parents who choose their child's genome through somatic-cell cloning will view the child as a commodity or an object to serve their own ends. What counts is how a child is treated after birth. Self-interested motives for having children do not prevent parents from loving children for themselves once they are born. Cloning would radically alter what it means to be human by replicating a living or dead human being asexually to produce a person with a single genetic parent.
Cloning represents the height of genetic reductionism and genetic determinism.
The egg cell now has a new nucleus, and it is the genome in the new nucleus that determines the development of the egg cell.