In Hairston v. Commonwealth, 2 Va. App. 211, 213, 343 S.E.2d 355, 357 (1986), the Court held that when an allegation of variance is based on unnecessary words in an indictment, the unnecessary word or words in the indictment must be descriptive of that which is "legally essential" to the charge. Stated another way, the unnecessary language must have a material effect on the offense charged and on the proof required to convict under that charge. Hairston, 2 Va. App. at 217, 343 S.E.2d at 359.