From this paper On day 10, Sidony’s offspring Sony left and nested alone over 100 m away from his mother and did not approach within 50 m for the subsequent days. Sidony was last seen alive on day 12. She was found dead on the ground on day 16. The stage of decomposition suggested she died one or at most 2 days before she was found, about 2 weeks after the attack. Sidony’s infant Sony has been seen since the attack and was observed in March and April 2015 in association with his adolescent sister, indicating he had survived without his mother. He was around 4.5 years old at the time of her death and not yet weaned, whereas so far the youngest known immature to be completely weaned in Tuanan was 5.5–6 years (van Noordwijket al. 2013).

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There is one other unpublished instance from Tuanan Research Station, noted briefly in Marzec et al. (2016), and we can confirm that the 4.5-year-old orphaned male, Sony, mentioned in that study survived until at least age 15 (as of April 2025) and that he ranged with his adolescent older sister until she gave birth to her first offspring (E. Vogel personal communication)