When you add a column to an existing table, it is added as the last column, i.e., the last ordinal position. The only way to add a column between existing columns is to drop and recreate the table.
Code that relies on ordinal positions, in general, is not a good practice. The recommended practice is to always explicitly list the columns. That said, I know many situations where it would be useful to do what you are asking for, but unfortunately, SQL Server does not allow that.