It is narrated from Sayyiduna Anas (may Allah be pleased with him) that when the Messenger of Allah (peace and blessings be upon him) prostrated in prayer, (Sayyiduna) al-Hasan or al-Husayn (may Allah be pleased with them both) would come and climb onto his (peace and blessings be upon him) blessed back, and because of this he (peace and blessings be upon him) would lengthen the prostration. So it would be said to him (peace and blessings be upon him): "O Prophet of Allah, did you lengthen the prostration?" And the Messenger of Allah (peace and blessings be upon him) would say: "My son had made me his mount, so I disliked hurrying him (to get down)."
The chain of this hadith is hasan (good), and on the basis of other supporting reports and corroborating chains this narration is sahih (authentic).
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب المناقب / 3970
Hadith Gradingمحدثین:إسناده ضعيف
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :إسناده ضعيف » «أخرجه سنن النسائي برقم: 1141، وأخرجه مسند أحمد برقم: 15603، وأخرجه المستدرك على الصحيحين برقم: 4828، 6690، وأخرجه المعجم الكبير للطبراني برقم: 7107، وأخرجه إتحاف الخيرة المهرة بزوائد المسانيد العشرة برقم: 6771»