Is a hadith with a weak chain of narration that is in the two Sahihs acted upon?

The student : If a hadith, meaning in Sahih al-Bukhari, is weak due to its chain of narration, is this text acted upon or not? For example, the hadith you mentioned regarding the etiquettes of the wedding in Sahih Muslim, where you stated that there is weakness in its chain. Do we use the text of this hadith as evidence or not?

The Shaykh : If a corroborating narration is found, it is acted upon; otherwise, it is not.
The student : Even if it is in Sahih Muslim?

The Shaykh : Yes, exactly.