1997 Toyota Camry Transmission Problem?

My mom has a 1997 Toyota Camry and one day she was driving it and it just started making a rattling and grinding sound and wouldn't go in forward or reverse or anything.

Everyone keeps telling me it is the torque converter and i think that sounds like the problem too but just wanted to be sure.

Like I said it is rattling and grinding when she tries to put it in gear and it doesn't move at all. Also when it is in park we have to put a brick under the rear tire to keep it from rolling.

If it is a bad torque converter does the whole engine need to come out to replace it?

Thanks