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I just began a reread and it seems odd that Prof. McGonagall was at Privet Drive--all day watching the Dursleys--yet did not seem to know that Dumbledore planned to leave Harry with the Dursleys. Indeed, she seems almost shocked when Dumbledore suggests he is leaving Harry there. If she was surprised at this, why would she be at 4 Privet Drive in the first place? Did someone tell her to be at that particular place? Did she know Petunia? Is there any canon-based explanation for this, and if not, any other explanations? Thanks.