5.—(1) This section has effect for the purposes of this Chapter.
(2) Two people (“A” and “B”) are personally connected to each other if any of these applies—
(a)they are, or have been, married to each other,
(b)they are, or have been, civil partners of each other,
(c)they are living together, or have lived together, as if spouses of each other,
(d)they are, or have been, otherwise in an intimate personal relationship with each other, or
(e)they are members of the same family.
(3) They are members of the same family—
(a)if B is A’s parent, grandparent, child, grandchild, brother or sister, or
(b)if—
(i)one of them is in a relevant relationship with someone else (“C”), and
(ii)the other of them is C’s parent, grandparent, child, grandchild, brother or sister.
(4) One person is in a relevant relationship with someone else if—
(a)they are married to, or are civil partners of, each other, or
(b)they are living together as if spouses of each other.
(5) In determining family membership—
(a)a relationship of the half blood or by affinity is to be treated as a relationship of the whole blood, and
(b)a stepchild of a person is to be treated as the person’s child.