it could have been left low from the oil change.
or
another common problem with these v8's is for the plenum belly pan gasket to fail, which sucks oil out of the lifter valley and burns it up. it can burn up a lot of oil over time. do a search on plenum for about a million posts. make your daughter check her oil ever time she gets gas. (its hard to do, they think that's somebody else's job).

 

At the rate she lost oil it would of been smokin like a chimney