Paul uses kinship language such as: brothers and sisters, children, and beloved.  He uses this type of language not to seem like he is above anyone, buth there equal.  The context that this usually appears in is when he is addressing large groups of people in his letters to the Thesalonians.  I feel like people would listen more if they were viewed as equals or brothers and sisters to Paul.  He also wanted to let people know that they were not alone in their faith in Jesus Christ.  They were all related to each other in some way vicariously through faith.  The relationship between the Thesalonians and the social and political world are pretty strained.  What I got from Paul is that the Thesalonians had to push through death and wait for the lord to save them.  Paul also says that the dead are not lost, but they will rise from the dead just like Jesus did on the third day.  1 Thessalonians 5: 1-11 is obvioualy a strike at the political power in the Roman Empire.  Paul said that when there is peace and security among the people, then Jesus will bring about sudden destruction to the people in power.