Settlor left all his property in a trust, with his wife as the income beneficiary for her life. At her death, the trust was divided among settlor's three surviving daughters. Settlor's will provided that each portion of the trust set aside for a daughter pay the income of that portion to her for life, and gave each daughter a testamentary power of appointment. One of the daughters, Isabella, did not expressly exercise her power of appointment in her will, although she had previously executed an instrument which limited the exercise of her power to descendants of settlor. In her will, Isabella left the residue of her estate to the issue of her sister, Margaret (D). If the will is construed such that, by naming Margaret's issue as residual takers, Isabella exercised her power of appointment in their favor, then they would take Isabella's share of the trust. If it is found that Isabella did not exercise her power, Margaret's issue would take one-half of Isabella's share of the trust, and the issue of her other sister, Jane, would take the other half. The trustees (P) have petitioned the court for instructions as to how Isabella's share of the trust should be distributed.