By Emeline Wuilbercq ADDIS ABABA, Jan 15 (Thomson Reuters Foundation) - Dozens of children are still waiting to be reunited with their families after crossing into Sudan alone to flee conflict in Ethiopia's Tigray region, aid agencies said, warning that they could be at risk of abuse, trafficking and child labour. More than 58,000 Ethiopian refugees have crossed into Sudan - about a third of them children - since fighting erupted in the northern region in November between federal troops and the Tigray People's Liberation Front (TPLF). The U.N. refugee agency (UNHCR) said more than 100 unaccompanied minors had been reunited with their families since the beginning of the conflict, but roughly the same number were still on their own in Sudan at the end of last year.