Gravely concerned at the lack of effective implementation of its resolutions 2139 (2014), 2165 (2014), 2191 (2014) and 2258 (2015) and recalling in this regard the legal obligations of all parties under international humanitarian law and international human rights law, as well as all the relevant decisions of the Security Council, including by ceasing all attacks against civilians and civilian objects, including ....... sexual and gender-based violence, as well as all grave violations and abuses committed against children,