@deborahl79_177961 or her son needs to determine if the oil is draining back into the pan correctly and this is one way to check. A more expensive way would be to remove the valve cover and visually inspect the oil drain back holes. Then they would need a new valve cover gasket set, which on this model ain’t cheap.
If the oil is draining back properly, then it is highly unlikely that there is much sludge build up in the engine. This is one of the first areas to clog up in my experience.