DH and I will be travelling very shortly without youngest DS (17). We wrote a will 11 years ago in which we named our proposed legal guardians. However since then, the relationship we had with those proposed guardians has ceased and in the interim we didn't get around to ever actually changing the will to reflect that.
In these circumstances, would it suffice to write a letter nominating a new legal guardian, to be appointed in the event of our deaths? Including signatures on the same letter from ourselves and our new chosen guardians so that it is clear that all parties consent?