Another existing project using ALSPAC data (B3397) is examining if religious and spiritual beliefs are related to healthy behaviours, disease end-points and biological biomarkers such as epigenetics. One possible way such associations may exist is that these beliefs may enhance the quality of intimate relationships either through shared beliefs and practices e.g. going together to a religious place of worship or helping to sustain them through difficult periods. This would imply that the quality of relationship may partially mediate the benefits. However, it is more complex than this as it is also possible that it is the relationship which also drives religious beliefs and hence this may confound any association. Furthermore both religious beliefs and relationships can change over time getting either stronger or weaker. We will use the repeat measures available in ALSPAC to examine these important questions.