For someone who is bulking, the "street science" says 1 gram of protein per pound of lean body weight is sufficient. So unless the parent weighs 400 lbs, 300 grams of protein is a gross overkill. Your body cannot metabolize that much protein.

Of course, some people are in the "better to have too much protein than too little" camp, which I guess works. But it's not a requirement by any means.