I came across more info for you. Abercrombie & Kent is an upscale tour operator and they offer "Egypt Family Holiday" tours which are geared towards kids and include a Nile River cruise. Their departures for 2002 are in March, July and Dec. I wasn't sure of your schedule. If interested, they can send you a brochure. Call: 800-323-7308.
Keep me posted on your plans.