Abu Dawud Book 2, Hadith Number 1304.
Chapter : Prayer and vigil at night.
Narated By Abu Sa’id Abu Hurairah : The Prophet (PBUH) said: If a man awakens his wife at night, and then both pray or both offer two rak’ahs together, the (name of the) man will be recorded among those who mention the name of Allah, and the (name of the) woman will be recorded among those who mention the name of Allah. Ibn Kathir did not narrate this tradition as a statement of the Prophet (PBUH), but he reported it as a statement of Abu Sa’id.