A child hangs upside down on a ladder while another child swings on a rope.
A young boy hangs upside down on a ladder while a young girl swings on a rope.
The word 'child' could mean any gender.  Nothing implies whether each child is a young boy or a young girl.
exists e1 p1 x1 x2 x3 x4 x5 x6.(on(e1,x6) & n_rope(x6) & while(e1,x4) & n_swing(x4) & of(x4,x5) & n_child(x5) & -(x4 = x3) & n_swing(x3) & of(x3,x1) & n_child(x1) & n_child(x1) & on(e1,x2) & n_ladder(x2) & exists s1.(r_upside(s1) & Theme(s1,x1) & a_down(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_hang(e1))
exists e1 p1 s1 s2 x1 x2 x3 x4 x5.(on(e1,x5) & n_rope(x5) & while(e1,x3) & n_swing(x3) & of(x3,x4) & n_girl(x4) & a_young(s2) & Theme(s2,x3) & on(e1,x2) & n_ladder(x2) & exists s3.(r_upside(s3) & Theme(s3,x1) & a_down(s3)) & Topic(e1,p1) & Actor(e1,x1) & v_hang(e1) & n_boy(x1) & a_young(s1) & Theme(s1,x1))