Life / How to address relatives from Poland properly? [3]

I'm visiting Poland in a couple of weeks and do not speak any Polish. We are on a guided tour. I have been learning the basics, hello, thank you etc. but on one day of our tour we will be meeting relatives who I have not seen for many, many years. How do I address them on meeting? One elderly lady has a little English so we will get by. Have limited our visit to a couple of hours as this is obviously not going to be an easy visit, but what is the correct way to say Hello. Its lovely to meet you after all this time? Or something appropriate?