No. 6 Birthday Girl

Some time ago I went to a restaurant with my good friend John. We were out with Sarah (John's daughter) celebrating her sixth birthday. My friend John is a good, law-abiding man who would object to anyone breaking the law, especially if it involved leading a child astray. While we were waiting for a table I asked everyone what they would like to drink, Sarah asked be to surprise her. Shortly after I returned from the bar with everyone's order including a strong alcoholic drink for Sarah, this was done in full view of John who did not object.

For this teaser you must explain why John did not object to me buying his daughter a strong alcoholic beverage on her sixth birthday.

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