 CONT: When Will complains about having to mow the lawn, Wills mom  tells him he used to do it all the time and had no problem with it  back home in Philadelphia. But in the last episode of season 4 "The  Philadelphia Story" when they go and visit Wills home in Philly,  there was no lawn to mow because he lived in an upstairs apartment.  And when they show the outside of the apartment building, there was  no lawn in the first place, just a concrete sidewalk.