The Montique family children were planning a 60^th wedding anniversary party for their parents.The children had decided to engage a local printing company to produce T-Shirts and hooded Sweatshirts that were to be specifically made for the Montique family to commemorate the event.They would have the family's name, their parent's names and the date of their wedding printed on them.The cost of the entire order was $450.00.Because the children do not live in the same town as the printer, they called the order in and orally agreed to pay for the merchandise over the phone.The employee, who was brand new, said that their order would be ready in two weeks.A day before the two-week deadline, the Montique family was shocked by the fact that their parents were getting a divorce, only two weeks before their 60^th anniversary celebration.The celebration was obviously cancelled and when the printing company called to tell the children that their order was ready, the printer was told that the merchandise was no longer needed and that no payment would be forthcoming.

What is the legal concept(s) being discussed? (There may be more than one.)