Continuity mistake: In the episode "The Fighting Irish", Jack's brother and father appear. Jack says "I haven't seen my father in 17 years." But throughout the rest of the series, it is mentioned many times that Jack's father ran away when Jack was little.
Continuity mistake: In the pilot episode, when Liz walks back into the writer's office Frank throws a sandwich at her, and she tells them to get it out of their system, i.e. throw things at her. We see all of the writers (Frank, Lutz, Toofer, Josh, a bald man, and a woman) grab various items off the table and the female writer grabs what appears to be an orange ball. When the shot changes to the objects hitting Liz, the ball does not appear. (It is not the bag of Cheetos, as you can tell it is made of some kind of foam.)
Answer: Maybe s02e14, "Sandwich Day"? Liz is talking to Floyd and asking if the girl who answered his phone has a lower back tattoo with a Chinese character that is suppose to mean "peace", but probably means "I have chlamydia." But nothing about it being a tribal tattoo.
Bishop73