Hi. my sister wants to know if it is possible for a 17 year old girl to grow 1 to 2 inches more. thanks! ?

It's possible, BUT: Growing often slows down dramatically post puberty. There is some chances though, as David Robinson (the Admiral) was a professional basketball player, who when he entered the naval Academy met their standards for height on ships, then grew a lot and was close to 7 feet, so the Navy had to change the rules for him!

Unlikely: The major driver for height originates in the long bones of the body, primarily the legs. When the growth centers of the legs have quit making new bone, as would be expected by 16-17y in a female, you're as tall as you will ever be. An x-ray if the hand can be used to demonstrate you're bone maturity & if the growth centers show open growth centers you may grow taller.If not you, re done.