This study aims to investigate the risk factors and protection factors associated with kinship foster care families (FF) who have overcome difficulties and been strengthened by their experience. Eighty-nine semi-structured interviews with kinship FF (foster carers) from four regions in Spain were conducted to identify the risk factors and protection factors that influence the stability of kinship foster care. Following analysis of the interview content, the results were separated into risk factors and protection factors related to the foster children (FC), the foster care families (FF) and the biological families (BF). The main risk factors for the FC were problems arising from mental and behavioral disorders and disabilities, problems related to foster care families' overprotection and to the negative perceptions of the FC, and problems arising from the BF inadequate relationship with the foster carers and their infrequent contact and relationship with their children. The main protection factors related to the FC were identified as their levels of autonomy, maturity and adaptability; for the foster carers, these factors were positive relationships with the foster child as well as the formal and informal support received; and for the biological family, these factors included a good relationship and contact with the child. Finally, it discuss the implications that protective and risk factors have for foster child, foster family and biological family.