Sahih Muslim 6588
صحيح مسلم#6588SahihNu'man b. Bashir reported Allah's Messenger (ﷺ) as saying:The believers are like one person; if his head aches, the whole body aches with fever and sleeplessness
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 45:86