I've never seen Leo on the verge of tears or blowing kisses to any of his other co-stars that may have been up on a podium. I don't think he blew Cate any kisses when she won the Oscar for The Aviator
They have such a special bond. He was elated for her and it shone through during that acceptance speech. He was thrilled when she won her first one, too! Remember, he gave her an extra kiss on the cheek when she got something from her purse.