Fort Sill: It is the home of the US Field Artillery. It is a large post with a big modern PX, but little else. The MPs are bored to death and ticket-happy, so watch your speed on post. Geronimo's gaurd house is located in the old part of the Fort with a lot of other frontier buildings, including a large walled corral that served as a sort of "keep;" a final defensive fortification in the event the post was overrun.
Lawton: big, flat, and dreary. Typical G.I. town with lots of pawnshops, fast food joints, bars, and strip clubs. If you like tatoos, you will have to travel to Texas to get one because it is not allowed in Oklahoma.
Weather: hot and humid in summer, cold in winter. Tornadoes are fairly common.
Good luck to you and your sister. The Lawton area can be a good place to live; it all depends on what you make of it. Treat yourself to a hamburger at "Whataburger," you will be glad you did!
Wichita Mountain Wildlife Preserve is a fantastic place if you like to rub elbows with rare wildlife. And the views from the mountain tops are spectacular. If I recall correctly, they allow a buffalo shoot once a year to keep the herd from outgrowing their food-source. The thousands of prairie dogs present are off limits, however.
Panzer Out