Why does the ghost mother insist that the little girl change her eyes into buttons? If not, can't she keep the little girl?

The essence of ghost mother is not to really "love" those children. Do you still remember the words of the black cat? "She is different from all the mothers I know." Ghost mother wants to keep the child, not to really make the child happy, but to imprison the child's soul to maintain life. The black cat said, "Maybe it's to eat you." Corlaine wants to know, "where can a mother eat her daughter?" Of course, this kind of "eating" is not really "eating", but to absorb and imprison the souls of those innocent children forever.

Sewing eyes means being controlled by a ghost mother, and eyes are like windows to the soul, so sewing eyes by a ghost mother means selling your soul to the devil (children are cheated by a ghost mother for a little benefit). All creatures in that unreal world are buttoned eyes, which means they are all under the control of Gui Mu. Another puppet father said, "Her strength is our strength".

Finally, when coraline got the souls (eyes) of three children, the outside world suddenly collapsed. It can also be said that the soul is not controlled by Gui Mu, and the magic fails instantly. And at that time, the ghost mother became more horrible than before, and the whole thing was a skeleton. When coraline took out the souls of three children, she couldn't help reaching for them, which also proved that Gui Mu could not live without the souls of the children.