Change font within sub

Nreports7

I have a report which shows surname or full name if a first name exists. I would like the first name to have a smaller font size than surname. If I use the procedure below I get the full name when I need it, but how can I change the font on the first name only?

 If Report.GetColumnValue("Register.FullName") <> "" Then

    NameText.Text = Report.GetColumnValue("Surname") + " (" + Report.GetColumnValue("FirstName") + ")"

   Else

    NameText.Text = Report.GetColumnValue("Surname")

   End If