Six-year-old Eitan Biran is at the center of a bitter custody battle after his parents and younger brother died in May when a cable car plunged to the ground near Lake Maggiore in the north Italy.
Members of his family were among the 14 people killed.
Relatives of Eitan in Italy claim the child was airlifted to Israel without their permission after being released from a Turin hospital where he received weeks of treatment for serious injuries.
Italian juvenile court officials had ruled he could live with a paternal aunt, Aya Biran, near Pavia in northern Italy – a decision that was allegedly challenged by the boy’s maternal family.
Ms Biran, who is a doctor with her own children, said the boy’s maternal grandfather took the child on an agreed day visit and then flew him to Israel without his permission.
She said when the grandfather came to pick up the boy on Saturday morning, he agreed to bring him back before dinner.
When they did not return, she reported the matter to the police.
Eitan was due to have follow-up medical visits this week and was undergoing physical therapy and psychotherapy, she said.
“Her bed is empty, her toys and clothes are left behind,” she said.
“His new desk, his school backpack, his notebooks, his pencil case and his books were ready. [for his first day in class on Monday]. »
Gali Peleg, a sister of Eitan’s late mother, denied the allegations, telling Israel’s 103 FM radio station: “We did not take Eitan. We will not use that word. What happened was we brought Eitan home.
She declined to reveal where the boy was staying in Israel and claimed he had “screamed in excitement” and said “I am finally in Israel” upon his arrival.
“Everything we did was for the boy’s sake,” she said.
Ms Biran told reporters she was “certain and hopeful” that the Israeli and Italian authorities would work together “to ensure her return home” to Italy.
Ou Nirko, a paternal uncle, told Corriere della Sera newspaper that the maternal side of the family had the boy’s Israeli passport and violated a court ruling by not giving it to his paternal parents until August 30.