Sayyiduna Abu Umamah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Whoever prays the Fajr prayer in congregation in a mosque and stays there until he prays the Duha prayer will have a reward like that of a pilgrim or one performing Umrah whose Hajj and Umrah are complete."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7632