Pop star Madonna has adopted twin girls from Malawi, announcing on social media she was "overjoyed" to bring them into her family. The singer, 58, was granted permission by Malawi's High Court this week to adopt the twin girls. She posted a photo on Instagram of herself walking along a rural path with the girls, who were wearing identical blue and white dresses and one wearing a hat. Madonna adopted Malawian children David Banda and Mercy James in 2006 and 2009.