We may feel jealous of a successful person, but we are never jealous of the success of our own children, even though they are someone other than us. When we see ourselves in the other person, love comes naturally. And where there is love, there is no room for violence, hatred, enmity, or jealousy. Love is a substitute for everything, but there is no substitute for love. And when that love becomes divine, there is no further need to say anything!

— Swami Tejomayananda

Why is somebody glad when their own child is successful but jealous when somebody else experiences success? Isn’t it the feeling of ‘mine’ and ‘other’ that makes the difference? I am happy if ‘my’ child succeeds but jealous when some ‘other’ person is successful. If a child that is born out of you is your own, then we are all children of the same God and belong to one God. We are all born out of the same source, live in the same space, and in the end go back to the same source. Ultimately, we all dissolve into each other. Then where is the question of ‘mine’ and ‘not mine’?

Swami Vivekananda says,

If a beautiful picture belonging to another is burnt, a man does not generally become miserable; but when his own picture is burnt, how miserable he feels! Why? Both were beautiful pictures, perhaps copies of the same original; but in one case very much more misery is felt than in the other. It is because in one case he identifies himself with the picture, and not in the other. This ‘I and mine’ causes the whole misery.

— The Complete Works of Swami Vivekananda, vol. 1, p.101.

‘I’ and ‘mine’ and ‘other’ is the cause of all misery. Drop the feeling of ‘mine’ and ‘other’ and simply enjoy success, appreciate beauty wherever you find it, and you will become the embodiment of success and beauty! ‘I’ and ‘mine’ and ‘other’ is mere illusion. When you drop ‘I and mine’, the whole world becomes yours. Then what remains is the feeling of oneness, pure Love. And when there is Love, where is the room for violence, hatred, enmity, and jealousy?

See also, How to overcome jealousy, hatred, rivalry and ego consciousness?