You shouldn't make people feel guilty.
Peg needs her coworker Beth to cover her shift at work, so that she may care for her sick son.
Peg wants to use her son as an excuse.
Peg tells Beth her son is sick and that she needs the extra time to take care of him.
Peg tells Beth her son is sick and that Beth is the only one that can help to cover her shift.
Beth is happy to trade shifts with Peg.
Beth feels unfairly pressured by Peg, causing her to be upset with Peg.