I would love to have Curtin's obituary if you are willing to share it. Through the research I have done I was pretty certain that John was Curtin's grandfather and that Sarah Vansickle was his 2nd wife. I haven't been able to bridge the gap between Melinda Street and Sarah between 1850 and 1860. Being able to positively prove that John was married to Sarah and even more so that he is in fact Curtin's grandfather would be so fantastic. Learning more about the Vansickle children and Joseph Burke would be great also. It sounds like you have more info than I but I would be happy to share anything with you that I could.
Thanks,
Mike