A man helps a boy steer a go-cart.
A father and son practice for the go-cart race.
You can not infer he is a father.
exists e2 e1 x1 x2 x3 x4.(Theme(e2,x4) & Actor(e2,x1) & v_steer(e2) & n_go-cart(x4) & Theme(e1,x3) & Actor(e1,x2) & v_help(e1) & n_boy(x3) & (x1 = x2) & n_man(x1))
exists s1 s2 x1 x2 x3 x4.(n_race(x4) & a_go-cart(s2) & Theme(s2,x4) & a_topic(s1) & subset_of(x2,s1) & for(x2,x4) & n_practice(x2) & of(x2,x3) & n_son(x3) & subset_of(x1,s1) & n_father(x1))