It's not true. Although some congressional employees are eligible to have up to $60,000 of student loans repaid after several years--just like other federal workers, this is not the case for members of Congress or their families. You can read more here about how this misinformation was spread, becoming the subject for a chain email campaign calling for a 28th amdendment prohibiting Congress from passing laws from which they themselves are exempt.
Hope this helps!
You're very welcome! Glad I could find this info for you.