An attorney represented a client in a case against the client’s former business partner. In her deposition, the client truthfully testified that she had lost her $100,000 investment in the partnership after her business partner negligently supervised the construction of a bistro (the business of the partnership). During the pretrial phase of the case, the business partner’s lawyer called the attorney and offered to settle the case for $15,000. The attorney became indignant, called the offer insulting, hung up the telephone, and did nothing further. What obligation, if any, did the attorney have under the Model Rules?