Remember that peoples memories are not infallible. Confirm the information you gather in one of these interviews with vital records whenever possible. Also, record the specifics of the interview on your research log. The interview is a source of information just like a book and should be noted accordingly. The informal interview is our favorite means of gathering information from family members because the opportunity presents itself so often.
Every family gathering becomes a potential source of information.
After a while, family members know of your interest in genealogy and will bring new information with them to these gatherings. This has worked well for us because we come from large families and the informal interviews have allowed us to remain current with births, marriages, and deaths of cousins and second cousins, even those from different generations. We carry copies of our family group sheets and ask an individual from a particular family group to look over the sheet and provide us with any updates. Obviously, family reunions are the best type of family gathering because they present the opportunity to see family members you may not have seen for some time. But weddings, holidays, baptisms, and visits offer the same potential.