My two cents….
The connection between all of this is the word 'family'.
What POTUS is doing with his tweet is that he is trolling Turkey. To be effective as a troll one has to give the person, in this case country, a hint about the information one has on them. POTUS is saying I know something about you, Turkey, that you don't want anyone to to know about that relates to 'family'.
Could be. If we add more from the tweet as a hint then we could say the troll could be about 'allowing return to the family'. Do more ideas come to mind?
Read a lot about human trafficking organ harvesting and the Syrian refugee camps in Turkey today, specially about children. With this in mind, returning to family would then add another layer to your theory.
Anon, I really think we are on the right track unless there is some major information we are missing…. something that has not hit the news yet… maybe something more obvious 'family'. I am thinking of the issue surrounding Erdogan's brother and the connection to ISIS (re: oil). Wonder where his brother is now.
Anon, please forgive me but I need to get some sleep. I have a big working day tomorrow. Maybe some other Anons have some more ideas we have not thought of.