My older sis is taller by 1 inch. We are both tall but I used to smoke in college and had menarche a year earlier. What cause my 'stunting'?

Not stunted. You & your sister are similar, but unless you are identical twins, your genes are not exactly the same. This may account for such a small difference in height. Also, the earlier you go through menarche, which is partially genetically determined, the earlier you are likely to stop growing. Smoking, if you didn't start until you were 18, probably had nothing to do with it, but if younger it might.