To children below the age of puberty and in the power of the testator, not only can such a substitute as we have described be appointed, that is, one who shall take on their failing to inherit, but also one who shall be their heir if, after inheriting, they die within the age of puberty; and this may be done in the following terms, 'Be my son Titius my heir; and if he does not become my heir, or, after becoming my heir, die before becoming his own master (that is, before reaching puberty), then be Seius my heir.' In which case, if the son fails to inherit, the substitute is the heir of the testator; but if the son, after inheriting, dies within the age of puberty, he is the heir of the son. For it is a rule of customary law, that when our children are too young to make wills for themselves, their parents may make them for them.

1 The reason of this rule has induced us to assert in our Code a constitution, providing that if a testator has children, grandchildren, or greatgrandchildren who are lunatics or idiots, he may, after the analogy of pupillary substitution, substitute certain definite persons to them, whatever their sex or the nearness of their relationship to him, and even though they have reached the age of puberty; provided always that on their recovering their faculties such substitution shall at once become void, exactly as pupillary substitution proper ceases to have any operation after the pupil has reached puberty.

2 Thus, in pupillary substitution effected in the form described, there are, so to speak, two wills, the father's and the son's, just as if the son had personally instituted an heir to himself; or rather, there is one will dealing with two distinct matters, that is, with two distinct inheritances.

3 If a testator be apprehensive that, after his own death, his son, while still a pupil, may be exposed to the danger of foul play, because another person is openly substituted to him, he ought to make the ordinary substitution openly, and in the earlier part of the testament, and write the other substitution, wherein a man is named heir on the succession and death of the pupil, separately on the lower part of the will; and this lower part he should tie with a separate cord and fasten with a separate seal, and direct in the earlier part of the will that it shall not be opened in the lifetime of the son before he attains the age of puberty. Of course a substitution to a son under the age of puberty is none the less valid because it is a integral part of the very will in which the testator has instituted him his heir, though such an open substitution may expose the pupil to the danger of foul play.

4 Not only when we leave our inheritance to children under the age of puberty can we make such a substitution, that if they accept the inheritance, and then die under that age, the substitute is their heir, but we can do it when we disinherit them, so that whatever the pupil acquires by way of inheritance, legacy or gift from his relatives or friends, will pass to the substitute. What has been said of substitution to children below the age of puberty, whether instituted or disinherited, is true also of substitution to afterborn children.

5 In no case, however, may a man make a will for his children unless he makes one also for himself; for the will of the pupil is but a complementary part of the father's own testament; accordingly, if the latter is void, the former will be void also.

6 Substitution may be made either to each child separately, or only to such one of them as shall last die under the age of puberty. The first is the proper plan, if the testator's intention is that none of them shall die intestate: the second, if he wishes that, as among them, the order of succession prescribed by the Twelve Tables shall be strictly preserved.

7 The person substituted in the place of a child under the age of puberty may be either named individually—for instance, Titius—or generally prescribed, as by the words 'whoever shall be my heir'; in which latter case, on the child dying under the age of puberty, those are called to the inheritance by the substitution who have been instituted heirs and have accepted, their shares in the substitution being proportionate to the shares in which they succeeded the father.

8 This kind of substitution may be made to males up to the age of fourteen, and to females up to that of twelve years; when this age is once passed, the substitution becomes void.

9 To a stranger, or a child above the age of puberty whom a man has instituted heir, he cannot appoint a substitute to succeed him if he take and die within a certain time: he has only the power to bind him by a trust to convey the inheritance to another either wholly or in part; the law relating to which subject will be explained in its proper place.