`关爱` is deeply embedded in Chinese culture, which often emphasizes collective well-being and social harmony. The concept reflects a hierarchical and responsible view of relationships, influenced by Confucian values. In this framework, those in positions of authority or strength (parents, teachers, leaders, the government) have a moral duty to show `关爱` to those under their charge (children, students, citizens, the less fortunate).
`关爱` is a common and very positive word, but it's used in specific contexts. It's more formal than everyday slang.