I don't want my daughter to learn Chinese along with her stepsibs from her step-mother
Doesn't that seem a bit unnecessary? Why don't you want your children to learn Chinese?
Because it will get in the way of her learning English, I want her to have a more competitive edge
I can see why you would want her to learn English first. Some children can learn both and it gives them a competitive edge too.
Oh yeah I guess she can learn Chinese after that.
I am glad you have realized that they can learn two languages at once, and it is actually better to learn two languages at a young age so that they would be more fluent when they grow up. I hope you make an effort to teach them daily life values too so that they would grow up being valuable members of our society.