A little boy is going to throw a ball on the beach.
A boy is tossing a ball to his dad.
The first sentence does not say what the boy is throwing the ball at, so we can't argue it was thrown at the boy's Dad.
exists e1 p1 s1 x1 x3.(n_beach(x3) & Topic(e1,p1) & Actor(e1,x1) & v_go(e1) & exists e2 x2.(Theme(e2,x2) & Actor(e2,x1) & v_throw(e2) & on(x2,x3) & n_ball(x2)) & n_boy(x1) & a_little(s1) & Theme(s1,x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_toss(e1) & to(x2,x3) & n_dad(x3) & of(x3,x1) & n_male(x1) & n_ball(x2) & n_boy(x1))