Angela Gunn was not actually pregnant during the shoot, but she had recently given birth to her daughter.
The interaction between the characters played by Angela Gunn and Roxanne Y. Morse was inspired by an actual incident observed by director Albert M. Chan between a pregnant woman and an elderly person carrying trash bags full of soda cans on public transportation.
The tattoo on the left forearm of Albert M. Chan consists of the Chinese characters for "true love."