The moment of truth came when Sheila and her 15-year-old daughter were having lunch with friends: "Mom, were you a virgin when you got married?" the teen-ager asked.
After a beat, Sheila admitted that she and the girl's father had had a "pre-honeymoon" trip, but quickly explained that they had wedding plans at the time.
Sheila, who like most of the parents quoted here asked that her real name be withheld, later admitted that she hadn't been completely truthful about her early escapades.
"It was 1969. 'Free love' was in. But I'm not proud of it now," she explained.
How honest parents should be in airing their past with children is tricky, experts say, and depends on a youngster's age and maturity, what he or she is asking and even a parent's motive in telling.
"Total honesty is good in the abstract, but it's not always appropriate," said Lois Gordon, an Encino marriage and family counselor.
Grown-ups tend to want to reveal too much, said psychologist Laura Schlessinger, who often fields disclosure questions from parents on her KFI radio talk show. Callers have wanted to divulge everything from their own past prostitution to the story of their child's conception through a sperm bank.
Schlessinger's advice: "Parents should give only the information that helps children grow and make better choices."
Many parents rightly fear that admitting past peccadilloes can give children a tacit go-ahead to behave the same way.
"I would be very quiet about my sexual past because you have to set an example," said Roslyn Rozbruch, 37, a Sherman Oaks mother of two girls, ages 6 and 2. "I wouldn't tell (my daughters) things that I wouldn't want (them) to do."
Jamie, an 18-year-old high school senior, proves the wisdom of this attitude.
She revealed that she loves to learn about her parents' past in order, she said, to "use it against them. Like when I got drunk and told my dad he couldn't get mad at me because he'd done the same thing in high school."
Another reason for keeping quiet involves parents' own privacy issues. One mom said she won't tell all because "I don't want my kids discussing my private life with their friends."
In addition, though, too much disclosure, especially about current issues such as dating, can make youngsters feel uncomfortable, said Gordon, as if no one is in charge. She said parents should examine their motives: " 'Why am I disclosing this? Do I want sympathy? Do I want my kid to like me or think I'm cool?' Those might be suspicious motives."
Also, she said, ask the child why he wants to know. "Sometimes they just want to tell you about something that scared them and asking is a way to open the topic."
An opportunity to explore a worrisome topic arose when Schlessinger's 8-year-old son asked if she had ever smoked marijuana. In Schlessinger's case, allaying his fears coincided with being honest: "I told him I had too much respect for my mind," she recalled. "We talked about how difficult it was because people razzed you if you didn't. We discussed how I got through the '60s without the drugs."
Gordon cited another example. If a child is feeling depressed or insecure, it may help for parents to acknowledge having felt that way once too. "You might say, 'I felt depressed in college, but I went to a therapist and although I was embarrassed at first, it helped me,' " Gordon said.
But even grown-ups with more lurid histories may choose to air the details. A Granada Hills father said he isn't comfortable with his children thinking he was perfect. He tells them the good as well as the bad about his college experiences with drugs and sex--especially since he fears a friend could leak the information anyway.
Such sharing of your past can give you credibility, said Charles Lerman, 44, a North Hills psychologist and father to four sons. "You don't want to lie to your kids, because on some level your child will sense it."
Some youngsters, of course, don't even want the lowdown on Mom and Dad. A Chatsworth high schooler was disgusted when she found out her mother once smoked cigarettes, and three junior high girls giggled when asked if they wanted to know about their parents' past sexual experiences.
"That's gross," squealed one.
Whatever a child's interest level, Lerman suggested that parents anticipate possible questions and decide ahead of time how to answer.
"Consider how comfortable you are in telling the truth," he said, and watch your child's reaction. Have they tuned you out or do they look shocked? "Ask them how they feel."
The important thing, Lerman emphasized, is to keep communication open because "if you have dialogue, you have a chance to make a difference."