朋友（綠卡）的姐姐（已退休）和姐夫準備來美旅遊，請教問題是：
1，她的姐姐申請資料時是否要填寫她妹妹家的資料？
-Yes. It is important to tell the truth and this will not affect her visa application.
是否就像其他普通旅遊一樣隻填他們的資料就可？
2，讓妹妹寫邀請信請他們來比較好？
-Up to her. If they will come with the tourist group, may not need the sister's invitation. Otherwise, it is helpful to have the invitaton letter.
好像資料要求比較多，較麻煩。
謝謝
