What is the protocol for a winging ceremony if your family cannot attend?

I'm assuming you are referring to a ceremony where service members are presented their aircrew wings. The answer is "it depends." Large groups such as a pilot training class, which I'm assuming numbers more than 20 these days, may be done in a formation or like a college graduation. In this case, the loved ones would wait until the ceremony is over to congratulate the new aviators. If the wings are presented to individual service members similar to a promotion ceremony, then the service member should choose whomever they want to help pin on the badge. Better yet a relative or friend who is a veteran. Perhaps an instructor who was particularly helpful to the student could do the honors.