Gift of residue to son's unmarried partner

I have client’s who want to leave the residue of their estates to each other and then to son and if he predeceases then to son’s partner provided that the son and partner are still together at the date of the testators death. Son and partner live together but are not married or in a civil partnership. Does anyone know of a precedent for this or is it simply " …provided they are living together at my death otherwise etc…" ?
sharon edelstyn
Phoenix Legal Group

This is a frequent problem. You don’t say if the partner is male or female, but assuming the latter, I first think that the ‘record date’ should be at the date of the son’s death (because if he and the partner were still living together at the parent’s death then the son would have inherited). So therefore I would try adding this as a condition relating to the gift to the partner:

“provided that [son] and Y were still living together as man and wife (whether or not they were married) at the date of [son’s] death…”

Jill MacMahon
Thackray Williams LLP