Great example with Edward the III.  It reminded me of Edward the 1st (Longshanks) whose army killed Simon of Monfort and desecrated his body afterwards.  Edward was raised for much of his childhood by Simon and was BFF’s with some of his sons.  Edward as crown prince supported Monfort’s provisions, but turned on him when he realized that he would be opposing his own father the King, Henry III.  Like you said in other words, blood is often thicker than friendship.

Yeah, Edward I was someone who approached relationships in a very instrumental fashion. He learned as much as he needed to from Simon de Monfort – the Model Parliament of 1295 was clearly modelled after Simon de Montfort’s radical parliament of 1265, and Edward clearly realized that a partial reform could bring about increased compliance and lower discontent – and then turned decisively against him to maintain the power and preeminence of the monarchy that he was about to inherit.