Kind emotions is originated from the heart. It has everything to do with Compassion, Empathy and Love. This is when you feel kind emotions towards everyone, even though sometimes someone says or does nasty things to you, but you know that person still needs to deal with their own internal suffering.
But unfortunately, this kindness is so fragile in these times full of negative stress, that it can be easily derailed. This is why it is best to practice these feelings and empower yourself through mindfulness, meditation or simply by cutting on the mental brainwash you are feeding yourself; so you enjoy these kind emotions more and more.