Collins was trustee for Indolent under the will of Indolent's father. Indolent, a middle-aged doctor, gave little concern to the management of the trust fund, contenting himself with receiving the income paid to him by the trustee. Among the assets of the trust were 100 shares of ABC Corporation and 100 shares of XYZ Corporation. About two years before the termination of the trust, Collins purchased the ABC stock from the trust at a fair price and after a full explanation to Indolent. At the same time but without saying anything to Indolent, he purchased the XYZ stock at a price higher than its current market value. At the termination of the trust, both stocks had advanced in market value well beyond the prices paid by Collins, and Indolent demanded that Collins either account for this advance in the value of both stocks or replace the stocks. What are Indolent's rights?