For eg.
GraphPlot[{1 -> 2, 2 -> 1, 3 -> 1, 3 -> 2, 4 -> 1, 4 -> 2, 4 -> 4}, VertexLabeling -> True]

Then If I remove the edge (say 1->4) and redraw the graphplot then I have

One can see the structure is not preserved. I want that looks like the same as the first one but without the edge 1->4. i.e., with vertices same at the coordinates as the previous one
My second question:
I noticed that if I have a huge graph drawn with the option of Graph not GraphPlot I am not able to resize the vertices. How can I resize them?

