well we know that Hermione n Ron are older than Harry coz in HP6, its said hat Harry cant take Apparition test coz he isnt 16 yrs yet...
n in POA its said that Hermy's b'day is in september when she sayd her mom n dad have given her money to buy a b;day gift and she buys Crookshanks...N In HBP...On Ron's b'day, he takes in the love potion from RomilDA vANE N Harry takes him to Slughorn..thats where Sluggy says that he is planning to gve the bottle of Butterbeer to DD on Christmas so Ron's B'day must be in Dec...
Just clearing my doubt😕
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