The 2011 Arab Spring destabilized national borders across the Middle East and North Africa, amplifying the dangers of migratory trajectories practiced by under-class Tunisian youth. Structurally locked out of national labor markets, young people took advantage of the security breach to attempt the Mediterranean passage to Europe; others migrated by the thousands to join the jihad in Syria, Libya, and Iraq. Back home in Tunisia, the figure of these missing youth became central to the politics of families left behind. Families foregrounded the inviolability of kinship in an appeal to the state to locate their missing kin, confirm their safety, and return them home. In this context, mothers’ gendered performances on behalf of missing sons are viewed as particularly efficacious.    This paper considers the pressures that kin-based activism places on mothers of missing Tunisian sons. Disappearance confronts families with an ambiguous loss: neither able to confirm a missing son’s well-being, nor properly mourn his death. Such mothers describe kin-bonds with their sons in terms resembling Sahlins’s “mutuality of being,” explaining how the sensorium shared between mother and son offers proof that the latter is still alive. While this helps mothers to navigate the uncertainty of ambiguous loss, it also risks making them the sole custodian of personhood for the absent son. This paper examines modes of emotional exhaustion among Tunisian activist mothers, revealing how the skilled performance of a boundless motherhood leads to depletion in the face of prolonged absence.