Abu Dawud Book 2, Hadith Number 1303.

Chapter : Prayer and vigil at night.

Narated By Abu Hurairah : The Prophet (PBUH) said: May Allah have mercy on a man who gets up at night and prays, and awakens his wife; if she refuses, he should sprinkle water on her face. May Allah have mercy on a woman who gets up at night and prays, and awakens her husband; if he refuses, she would sprinkle water on his face.