I grew up in a home where many were very open about sharing many details about our lives. That transparency and easy share was familiar to me. On the other hand, I had friends who grew up in homes where little information was shared--many of the details related to their families were quite secretive. My friend's family and mine were probably closer to the opposite ends of the transparency/share continuum, and everyone else I knew fell somewhere between those continuums. Is it good to be open about your life or is it best to be more closed and secretive? As with almost all of life's issues, I don't think there's one answer to this question, and I think that to strike a good balance is the best answer.
When is openness positive?
When families operate with lots of secrets, those secrets can eventually become a cancer because few secrets stay hidden over time. In many ways, it's a lot more difficult to find out the truth of the matter long after you can do anything about it and hidden truths can be very hurtful and harmful. I remember hearing a story about someone who was wrestling whether to tell family members a secret she held--the woman looked out into the future, and made the decision that it was better to share the secret earlier than later. Typically young children are able to understand and accept information better than teens or young adults, so I think the woman made a good choice.
On the other hand, if you have tough or controversial information about yourself or others, sharing that information can affect the way people think about you or treat you. Sometimes it's best to keep the bad or tough news about yourself or your decisions quieter on the public front. I noticed that recently when I shared a personal truth with an old friend. When I saw her reaction, I realized that it probably wasn't the best idea to share that information since she had not context with which to understand it, and it probably did affect the way she thinks about me in a not so positive way.
Hence there's a balance when it comes to what we share about ourselves and our families--too many secrets can eventually be harmful and hurtful, but too little privacy can cause undue stress and negative ramifications.