Datagridview InsertAt

[inpuarg]

I have 2 column :
Column1 Column2
A 25
B 20
C 15
D 10
E 5

After i load form, i move current cell to D and my currentcell.rowindex is 4
grid.CurrentCell.RowIndex = 4
Then i sort by clicking column2 . And my currentcell.rowindex is 2.
I add a row by using insertat function :

DataSet ds = (DataSet)grid.DataSource;
DataTable dt = ds.Tables[0];

DataRow row = dt.NewRow();
row["ID"] = System.Guid.NewGuid().ToString().ToUpper();
dt.Rows.InsertAt(row, base.CurrentCell.RowIndex + 1);

But due to sort order this row goes to first row.
I don 't want this. I want that empty cell to locate 3 'rd row.
How can i customize that sort and implement this feature ?