With the development of the economy and advancements in medical science, the average life expectancy of the population of China has increased substantially , as well as the number of elderly people . According to China’s seventh national census (2020), the population of 60 years and older is 264.02 million, accounting for 18.70% of the entire population (of which 190.64 are aged 65 and older, accounting for 13.50%). Compared with 2010, the proportion of the population aged 60 years and older has increased by 5.44% . As the process of urbanization has accelerated , population migration has continuously increased in China , reaching 375.82 million in 2020, of which 124.84 million represent the inter-provincial mobile population. Compared with 2010, the migrant population after ten years has increased by 69.73% . Reflecting the traditional Chinese culture, some elderly people moved to new cities with their children to help caring for their grandchildren ; henceforth, “migrant elders following their children” (MEFC). With the implementation of the universal two-child policy in 2015  it was expected that there would be more MEFC in China.
After the MEFC left their hometown moving to new cities, the social context and daily living environment changed, which push them to adapt to the new environment and go through the re-socialization process. This may have caused a series of problems with the MEFC, such as difficulties in social integration , slow social adaptation , reduced utilization of medical services , decline in health status , lower or no medical insurance reimbursement ratio in the new cities , higher depression and loneliness, separation of registered and actual residences, lack of essential public health services , and social welfare inequality . All these issues affected the health status of MEFC and the development of their families, and have become an important social problem that needs to be urgently solved .
Loneliness is a state of distress, depression, and detachment due to the emptiness of a person’s social and/or emotional life . Loneliness may occur in people of all ages, especially in the elderly [18–20]. It is negatively related to their physical and mental health, and can lead to physical discomfort, poor prognosis, and be accompanied by cognitive decline, depression, stress, and anxiety [21–23]. Loneliness could also increase the risk of suicide and impair the quality of life [24, 25]. Research on the loneliness of migrants in China mostly focused on workers and children, and less attention was paid to the elderly [26–29], while the level of loneliness among the latter has increased in recent years .
Life satisfaction refers to wellness in relation to several dimensions, such as happiness, peace, self-confidence . Previous studies on the life satisfaction of Chinese people mostly focused on migrant workers, few considering the elderly migrant, who were more vulnerable within social interactions and emotional states [32, 33]. Older immigrants completed life cycle stages, such as work and parenting, which can cause dramatic changes in the short-term satisfaction . Studies have shown that most senior immigrants believe that their life satisfaction would remain stable or even improve over time . However, the migration process would seriously affect their life satisfaction, especially of those who migrated from rural to urban areas within China . However, it was revealed that elderly immigrants whose families are reunited tended to show higher life satisfaction . And research of elderly residing in nursing homes in the Philippines suggests that life satisfaction of the elderly could influence their loneliness .
Childcare disagreements with children refer to the conflicts between MEFC and their children generations in the care of the grandchildren generations. Research in Taiwan showed that long-term multi-generation caregivers were more likely to report higher life satisfaction and fewer negative psychological changes when compared with non-caregivers . By contrast, other studies demonstrated that living with children and caring for grandchildren are more likely to cause adverse health consequences for the elderly, and grandparents who cared for grandchildren were more likely to experience feelings of depression and isolation [40, 41].
But there was no research to explore the impact of life satisfaction on loneliness in MEFC Therefore we proposed to assume that life satisfaction had a relationship with loneliness, and further we explored the relationship between childcare disagreements with children, life satisfaction, and loneliness of MEFC in Jinan, China.