A year later Bridget prepares to be married. At the altar she is greeted by Jack, holding her son, and then moves forward to marry Mark. After the wedding, Mark and Jack, now friends, head to the reception together while Bridget carries her and Mark's son, William.\n\nWho is the daddy in bridget jones baby?
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The relevant information to answer the above question is: After the wedding, Mark and Jack, now friends, head to the reception together while Bridget carries her and Mark's son, William.
So, the answer is Mark.
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