What is the test for establishing that a parent is entitled to a trust fund for life with the remainder of it to his daughter when she marries?

In Plunkett v. Lewis (1844)3 Hare 316, 67 E.R. 403, the father was entitled to a trust fund for life with the remainder to his son and daughter. He sold the fund and when the daughter was married he settled property upon her, the value of which was greater than that which she would have received from the trust. "Now the rule as stated (2 Roper, Leg. 57) and, I believe, correctly stated, is this: that, where a debt exists from a parent to a child, 'an advancement upon the child's marriage, or upon some other occasion, of a portion equal to or exceeding the debt "in the parent's life shall prima facie be deemed a satisfaction.' I think this presumption, in the abstract case, is just and reasonable. If a debtor pays his creditor a sum equal to his debt, the presumption must be that he intends by the payment to discharge the debt; and if, instead of paying it into the hands of the creditor, he pays it to another for the use and benefit of the creditor, as part of a transaction to which the creditor is a consenting party, the presumption in the abstract must be the same." (p. 405) ( emphasis added)

In the case at bar the father incurred an obligation to benefit the son by way of a divorce settlement. In the father's lifetime he has as a result of the 1961 trust agreement transferred to the son a total number of Conick shares in excess of that which he was required to transfer under the 1959 agreement. The principles which apply to the marriage settlement cases may also apply in this case to the extent that, in the words of the Lord Chancellor in Wood v. Briant supra, it would be "unnatural" to suppose that the father intented to benefit the son to the extent that he would receive the full number of shares set out in the 1959 agreement in addition to the shares he received as a result of the 1961 trust. I would not go so far, however, as to say that in this case there should be a prima facie finding of satisfaction, given that the obligation was incurred under a divorce settlement for the benefit of a third party.