Private Sub ReplacePattern()

        Dim strTxt As String
        Dim rgxExp As New System.Text.RegularExpressions.Regex("\d{2}/\d{2}/\d{4}")

        strTxt = "Alison, DOB 01/01/1961; Bryan, DOB 12/13/1969"
        strTxt = rgxExp.Replace(strTxt, "XX/XX/XXXX")

        MessageBox.Show(strTxt)

    End Sub