Is it normal to share drinks with family?
Depends.It depends
Yes, plenty of families share drinks, while others find it gross. It mostly comes down to family habits and how comfortable you are with it.
Lots of families casually pass around a drink or take sips from the same cup. Other people prefer everyone to have their own, and neither preference is strange.
The practical caveat is that sharing cups can pass along germs, so it’s sensible to avoid it when someone’s sick. Otherwise, it’s mainly a matter of comfort and household custom.