Anxiety Symptom

When they ask their doctor is there a reason why they are losing weight, the doctor's reply was no there is nothing wrong, but I do know that this person had been going through a lot of stress with so much things lately. They haven't had much of an appetite but when this person is not stressed out they can eat without any problems like throwing up and they can gain weight (it takes time for them to gain weight I guess because of their metabolism). This person has also lost sleep because of stress.

There is a family member I have who is ill. The family member had lost a lot of weight themselves and also they are going through a lot of stress too. Their relationship is not so good and there is other terrible emotions they are having.

That could be a contributing factor. She might have to consult with her doctor to find out for sure

They can be but the person should see a doctor to make sure nothing else is wrong.

If it's the result of a lack of appetite and eating less.

Yes, i lost almost 30 pounds

Some people lose their appetite when stressed/depressed.