"Listen, we're all *possibly* Frank Sinatra's son," Ronan Farrow tweeted last week.
The lighthearted message masterfully sidestepped gossip and scandal: His mother, actress Mia Farrow, divulged to Vanity Fair magazine that ex-husband Frank Sinatra could "possibly" be the 25-year-old's father. It was long believed that the biological father of the Rhodes Scholar-turned-diplomat-turned-lawyer was filmmaker Woody Allen, who had a relationship with Farrow for 12 years.
Ronan Farrow fell out with Allen when it came to light that the prolifically quirky director was having an affair with one of Mia Farrow's adopted daughters, Soon-Yi Previn. Allen and Previn later married in 1997. On Father's Day last year, Ronan memorably tweeted: "Happy Father's day -- or as they call it in my family, happy brother-in-law's day."
While this most recent questioning about paternity made headlines because of the famous parents, the circumstance can shake any family, according to psychology experts. Families shaped by divorce and remarriage, traditional adoption, second-parent adoption, surrogacy and in vitro fertilization might mean the conversation happens more often than ever before.
'The world opened up'
For Brian Hansen, 32, of New Jersey, his life changed over a drink with a cousin in 2010.
Hansen and his wife were expecting their first child, and he told his cousin he was scared of the type of parent he would be because of the angry father he had known.
"My cousin saw that I was very worried and in a distressed place," Hansen said.
His cousin, sensing his angst, figured it was time to come clean: The man who had raised Hansen was not his biological father. Hansen's mother had used a sperm donor to conceive both him and his younger sister.
"I just sat there and stared at him for nine or 10 seconds," Hansen said.
"... My life literally re-defined by fermented oats served cold by a waitress with nose jewelry named Miranda," he wrote on his blog less than 24 hours later in a post titled "And Now For Something Completely F***ed."
For Hansen, there was an immediate sense of relief. From about age 7, Hansen said he and his sister would look at each other and ask: "Where did we come from?"
He had a rocky relationship with his father growing up, and in 2008, he severed ties once and for all. His parents, now divorced, were together for 32 years.
"Once I found out I wasn't beholden to his gene, the world opened up," Hansen said.
While Hansen's and Ronan Farrow's paternal relationships fell into the "strained" camp, experts such as Jennifer Hogan say the news can rock a family whether the parent-child relationship is good, bad or downright ugly. This type of news will raise issues of identity and trust, especially if other family members were in on the secret.
"It shakes your self-awareness and sense of self to its core," said Hogan, a licensed clinical social worker. "For parents, the important thing to understand is that we get a lot of identity from who our immediate family is."
Think about it: Recreational hobbies, personality traits, even career paths often follow the suit of a parent.
"The child starts to feel like an outsider to their family," Hogan said.
Hogan said Hansen's sense that he "wasn't destined to become the same as this person" can be freeing: "You get a clean slate for half of your biology."
But there will also be some uncertainty about what traits might come from a newly discovered parent.
"It will shake your foundation," psychiatrist Gabriela Cora agrees. "Even if you suspected it before, confirming it can still be a shocker."
'Secrets are inherently destructive'
For parents, of course, the million-dollar question is when to deliver the news.
"Secrets are inherently destructive to families," Hogan said. "Eventually they come out, and they cause a lot of havoc."
The debate over disclosure versus secrecy is one that adoption support groups advise should be ongoing within families -- and that the child's age and inquisitiveness are cues for how much to make known. There's no easy answer.