Authentic
Muttafaq ‘alayh (Bukhari and Muslim) Sahih al-Bukhari 6092
I have never seen the Prophet (may Allah's peace and blessings be upon him) laughing so heartily to the extent of seeing his uvulae; rather, he would only smile.
مَا رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم مُسْتَجْمِعًا قَطُّ ضَاحِكًا حَتَّى أَرَى مِنْهُ لَهَوَاتِهِ، إِنَّمَا كَانَ يَتَبَسَّمُ.
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