1998 Chevrolet Prizm

Engine Mechanical problem
1998 Chevy Prizm 4 cyl Front Wheel Drive Automatic 124000 miles

My brother in law borrowed my car for vacation because he didn't trust his. Ironically, it broke down on the way home, 30 miles from his house. Just got the info from the mechanic, thrown rod, needs a new engine. Questions:

1. How likely is it that my brother in law may have caused this, or is this just something that would have happened to me eventually?
2. Before this I had a 97 Geo Prizm that I gave to my in-laws. Can this engine be used in my 98 Chevy Prizm? If so, what kind of cost are we looking at to swap them out.
3. What kind of cost am I looking at to replace the engine with a used/rebuilt/new engine?

Any advise would be greatly appreciated.
August 13, 2010.

It is VERY unusual for a Toyota engine to throw a rod, unless it is low on oil or driven with low coolant.
Or engine was overrevved for a considerable distance.

Check with local junk yards for interchangeability between years.

Swapping an engine would usually be $600-900 in labor depending on who does it (dealer vs. Trusted garage).

Aug 17, 2010.