Rear Suspension Leaf Spring Leaf problems of the 2002 Nissan Xterra

The main leaf spring in the rear suspension sheared off next to the axle while driving. I was the only person in the car and the total load in the rear of the car was approximately 100lbs. The spring caught on the brake line as it broke. My abs light came on. The repairs have not been made yet.

I own a 13 month old 2002 Nissan Xterra that has 32,600 miles on it and has never been driven off-road. The leaf spring on the driver's side broke at the rear mounting bolt. Luckily we caught it immediately and the dealer is replacing it under warranty. Has this been a problem with the Xterra and should the other one be replaced at the same time? the dealer claims to have looked at the other one and sees no problem at this time. I'm concerned about the safety because I do a lot of high speed driving with my daughter in the car.