The Air France KLM Flying Blue Program rules state that “the Flying Blue account, the XP, the level and the Miles earned by the concerned Member cannot under any circumstances be transferred, bequeathed, assigned, sold or combined, whether or not for valuable consideration, with the account of the Miles of any other person whether or not that person is a Member of the Programme, or with any other account belonging to the Member, except as otherwise provided by the Company and specified in Flying Blue Communication.” This would possibly give one some hope. But then further says….
“In the event of the death of a Member, the Company shall close that Member’s account and cancel all Miles and/or XP earned by the concerned Member upon receipt of the death certificate.”
So my guess is that the Miles do not pass upon death.