Harry Potter and the Chamber of Secrets

Do you have a copy of Harry Potter and the Chamber of Secrets handy? My edition was published in 1990 by Raincoast Books and on page 245 it says this:

You can speak Parseltongue, Harry,' said Dumbledore calmly, 'because Lord Voldemort - who is the last remaining ancestor of Salazar Slytherin - . . .

". . . ancestor? "

Could you check your edition? What does yours say? This passage is in the chapter Dobby's Reward about a page before Lucas Malfoy shows up.