What did the Prophet Muhammad (saw) say when he found out that Ali and Fatima had not prayed Tahajjud?
 Narrated `Ali:                     That one night Allah's Apostle came to him and Fatima and said, "Don't you (both offer the (Tahajjud) prayer?" `Ali said, 'When Allah wishes us to get up, we get up." The Prophet then recited: 'But man is more quarrelsome than anything.' (18.54) (See Hadith No. 227,Vol. 2)