Milk or Blood from Fingers
Scholars have said that if one dreams of milk coming out of their thumb and blood from their index finger, and they drink from both, it may indicate their involvement with his wife's mother and sister. They also mentioned that cracking knuckles in a dream might signify unpleasant talk among relatives.
Per Ibn Sirin's Muntakhab al-Kalam fi Tafsir al-Ahlam
Note: These are traditional scholarly interpretations (ijtihad) drawn from a specific classical source — not a binding religious ruling, fortune-telling, or a prediction of the future.