Dad enjoying with his in the swimming pool.
Dad happily enjoying the swimming pool
Someone enjoying something doesn't infer that they are happily enjoying something.
exists e1 x1 x2 x3 x4.(n_pool(x3) & of(x3,x4) & n_swimming(x4) & ne_nam_dad(x1) & in(e1,x3) & with(e1,x2) & n_his(x2) & Actor(e1,x1) & v_enjoy(e1))
exists e1 s1 x1 x2 x3.(n_pool(x2) & of(x2,x3) & n_swimming(x3) & ne_nam_dad(x1) & a_happily(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_enjoy(e1))