Judgment unanimously affirmed. Memorandum: We note that the trial court's ruling, foreclosing the People from introducing through a rebuttal witness evidence contradictory of defendant's testimony and that of his character witnesses as to how he treated his and other children, was erroneous. It is well settled that once a defendant has introduced evidence of his good character, the prosecution may prove his bad character by cross-examining him and his witnesses and by calling rebuttal witnesses ( People v. Kass, 25 N.Y.2d 123; Richardson Evidence [9th ed.], §§ 156-158). In addition, the District Attorney's offer of rebuttal testimony had a reasonable basis and was made in good faith, and did not constitute error ( People v. Kass, supra; People v. Schwartzman, 24 N.Y.2d 241, 244).