Lillith nodded and waved as Barrel left, relieved that he had caught on and been relatively subtle about the presence of alcohol and invitation to bring wine. She then turned to Vlad and politely requested to take a bottle or two of blood wine. 

It took a bit of persuasion, but eventually her father acknowledged that one bottle diluted in another [public? shared?] beverage likely wouldn't cause anyone to become inebriated enough to cause too many problems. He also trusted Lillith to keep herself well below her limit, and ensure everyone at the party maintained a certain level of decorum. Carmilla... Well, he at least trusted her not to get out of hand in front of other people.