My friends 8 yr old sister had first panic attack. parent not doing nothing about it. will she have more? my friend said not big deal.

Possibly, especially: if there is a family history of anxiety disorders. There is nothing you can do but share your experience with the discomfiting nature of childhood anxiety, if the parents are receptive. Some families do not disclose psychiatric care to friends & extended family. That is their right, even in this "Age of Oprah".

Panic attacks: The answer the the question, "will she have more?" goes back to the fact that she already had one. She needs to be assessed by a professional, such as a child psychologist or psychiatrist, and given treatment if needed to prevent any further problems from developing. A parent needs to be involved in this process, and might need treatment him or herself.