Should I tell higher up?

I work nights. My shift manager is only 20. She got another employee to buy her alcohol during our shift. She leaves with him (which we have to have a manager at the store at all times) and when she gets back she drinks it in her vehicle during shift. She usually goes out to her car several times a night for anywhere from 30 minutes to over an hour with another coworker to smoke pot. We are short staffed and can get pretty busy and they will stay out there. They are parked at a spot where they can see when/how busy it gets. Higher up has told me to let him know when she is outside for a long period of time.

Should I mention what she does when she is outside and that she drank during shift?

She mentioned out loud that she wanted to drink, when she left, where she was going . She mentions she smokes and I've had to go out to ask her to help us inside that's how I know she smokes during shift.

*I have no problem with people smoking pot or drink*