One Ghusl is enough for two occurrences of Janabah

Q 2: I am married. Once I slept and had a sexual dream. I saw in the dream that I had intercourse. When I woke up, I took a bath and washed my private parts, then slept with my wife and had intercourse. Am I sinful?

A: All praise be to Allah Alone, and peace and blessings be upon His Messenger, and his family and Companions! If the reality is as you mentioned, you are not sinful for having a sexual dream. You should perform Ghusl (ritual bath following major ritual impurity). You should also perform Ghusl after having intercourse with your wife. There is no harm if you delay performing Ghusl until you have intercourse with your wife and then perform one Ghusl for both the sexual dream and intercourse. (Part No. 5; Page No. 302) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.