Section 643H | Meaning of close member of settlor's family in sections 643A to 643EA
From legislation.gov.uk
(1)For the purposes of sections 643A to 643EA, a person is a close member of the family of the settlor of a settlement at any time if the settlor is living at that time and—
(a)the person is the settlor's spouse or civil partner at that time, or
(b)the person—
(i)is a child of the settlor, or of a person who at that time is the settlor's spouse or civil partner, and
(ii)at that time has not reached the age of 18.
(2)For the purposes of subsection (1), two people living together as if they were a married couple or civil partners are treated as if they were spouses or civil partners of each other.