 PLOT: In the safe deposit box, there is a letter addressed to Cheryl  which references Alfies first wife, who was killed in 1916.  Throughout the movie, though, its clear that Michael is the son of  Christina Alperin, not the first wife, which should make him, at  most, 13 during the events of the movie. One could argue that since  Alfie is not the biological father, Michael could have been a child  or teenager when Christina and Alfie married. However, that wouldnt  make sense in the world of the movie because Michael doesnt seem to  be aware that Alfie is not his father.