Donald and David Moss, 51, of Saanich, British Columbia, got the news Sunday, The Victoria Times Colonist reported.
Donald's daughter-in-law Ashley gave birth to Malia Moss at 4 a.m. at Victoria General Hospital, and at 1:25 p.m., David's daughter Catherine MacDuff bore Georgia Teresa MacDuff. Their rooms were on the same floor.
Ashley was a few days past her due date and Catherine a few days early.
"They both have really dark hair," said David. "Both are just beautiful little girls, so we're pretty happy."
Malia's parents are Shane and Ashley Moss, who have been married for less than a year. Georgia's parents are Matt and Catherine MacDuff, who have been married slightly more than one year.
Matt MacDuff, an identical twin as well, said he predicted two months ago that his baby would be born Nov. 21, one month after his own birthday.
The babies are the third and fourth great-grandchildren for Bob and Marie Moss, 86 and 85, respectively.