Can you exchange an airline ticket for one on another flight of the same airline?

My daughter went on vacation with a friend. She's decided that she doesn't like the trip and wants to come home. Her return flight is next Tuesday but she wants to know if she can exchange the ticket for a flight home from the same airline on Friday? I told her I had no idea. Can anyone help?

If I understand, she wants to come home early. In that case sure you can do that, call the airline and tell them your at where ever, you return on this day and you want to come home this day, they will book your early flight for you, but expect to pay a fee.