Simply so, what is it called when you keep someone on a string?
To maintain great influence over one. If you want to keep someone on a string, flattery always helps.
Similarly, what does it mean to keep someone on a silver string? to have control or a hold over (someone), esp emotionally. See full dictionary entry for string.
Also asked, where did the term hanging by a thread come from?
The term hanging by a thread, derives from the banquet that King Dionysius held for Damocles, a courtier of ancient Syracuse. He invited him to a banquet, where Damocles was seated under a sword suspended by a single hair. It was said to symbolize his tenuous position in the court.
How do you hang a thread?
If a serious situation hangs by a thread, it means that even a slight change can decide what will happen and that a bad result such as death, failure, etc. is likely: The mayor's political future has been hanging by a thread since the fraud scandal.
