Here's what Paul said--sorry, I only have the KJV at the moment:
Rom 8:28 And we know that all things work together for good to them that love God, to them who are the called according to his purpose.
Rom 8:29 For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren.
Rom 8:30 Moreover whom he did predestinate, them he also called: and whom he called, them he also justified: and whom he justified, them he also glorified.
Rom 8:31 What shall we then say to these things? If God be for us, who can be against us?
You asked: "...did God know that we would be able (persevere) to be sons/daughters of God? Or did He just make the chosen this way?" Clearly He KNOWS and KNEW, but I'd rephrase your question to say that He IS MAKING those who are "enduring to the end" to endure to the end, just as He MADE those before us who endured to the end to do so. It is "HE Who is working in us both to will and to do His good pleasure". So NO, no mortal can take credit for what we go through in being conformed to His image...but we will be conformed to His image and go through that transformation. The question is not 'whether or not', but 'when'.