Sa’d bin Hisham narrates this statement from Sayyidah Aisha (may Allah be pleased with her): Whenever the Prophet (peace and blessings be upon him) performed any prayer, he liked to perform it regularly. And if, due to sleep or illness or any other engagement such as difficulty, he was unable to perform the night voluntary prayers, then he would perform twelve rak’ahs during the day.
Hadith Referenceصحیح ابن حبان / كتاب الصلاة / 2552
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - مضى (2411). تنبيه!! رقم (2411) = (2420) من «طبعة المؤسسة». - مدخل بيانات الشاملة -.فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح على شرطهما