What is the interpretation of the recurring dream about marriage, and is it a result of Istikhara or mere contemplation?

Dreams and visions are of three types: those that are from Allah, the Most Merciful; those that are from Satan, the devil; and those that are self-talk, reflecting the sleeper's thoughts. It appears that the sister is attached to this man, and her dream of being with him reflects her desire to marry him despite her parents' disapproval. The advice is to fear Allah, obey her parents, and ask Allah to grant her a righteous husband.