It is narrated from Hazrat Amr (may Allah be pleased with him) that once we were on a journey with the Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) slept at the time of Fajr, and no one could wake up until sunrise. Then the Prophet (peace and blessings be upon him), making up for it (qada), first offered the two Sunnah (rak'ahs), then established the prayer and led the Fajr prayer.