When the end credits rolled for 51 Birch Street and I saw a thank-you to documentary filmmaker Ross McElwee, I thought, "Aha! I was right!" It is one thing to guess about potential influences while watching a film, but much more gratifying to receive concrete proof validating your suspicions. Doug Block's latest film is more of a personal journey than a traditional documentary, and his debt to McElwee is evident.

51 Birch Street is about Block's own family, and is narrated by Block. The film opens with footage of his parents that he shot shortly before his mother died, in which his mother talks about her life and her marriage quite contentedly. Block shot this footage for his personal use, with no idea of how he might use it later.

Three months after Block's mother died, his father travelled to Florida to see Kitty, who had been his secretary decades earlier. They fell in love and were married not long afterwards. Block's father then decided to sell the family home (the 51 Birch Street of the title) and move to Florida.

In the wake of these events, Block starts to wonder about his family, particularly his father, whom he feels he does not know very well. Did his father have an affair with Kitty all those decades ago? Was his father happy in his marriage to Block's mother? He interviews family and friends, realizing that he knows very little about his parents' relationship.

As Block delves into research about his own family, he discovers his mother's paper journals—she wrote daily about her life in the late 1960s and early 1970s. He has to decide whether he should read these journals ... and once he does, he is faced with surprising revelations about his mother's personal life.

51 Birch Street is not only a glimpse at Block's family history. From a wider perspective, it is an examination of the way families communicate—or don't, whether they're young couples or families with grown-up children. I don't know whether the best lesson from the documentary is to communicate more with your family ... or to burn your personal diaries. The film also provides a look at the ways in which marriage has changed in the past half-century, and shows how various people deal with a death in the family.

Block's film contains very few slow spots. He manages to present the excerpts from his mother's diaries in an interesting visual way that accentuates some of the key phrases that affected him. He also delves effectively into family mysteries without offending or showing disrespect to any of the parties involved.

This was a difficult movie for me to watch, for a number of personal reasons. But I suspect that many of us would find a personal connection to 51 Birch Street—at the screening I attended, the film had an emotional effect on many audience members.