A poll of 2,000 adults found just 29% know who their mum first dated, and even fewer know about their dad's early love life (19%). Yet, 34% could correctly identify Chelsy Davy as Prince Harry's first high-profile girlfriend. While 26% knew Wayne Rooney's first car - a Ford SportKa - but only 21% could say the same of their mum's.
The survey was commissioned by National Rail, on behalf of the rail industry, which has launched a new version of '36 Questions' to help people find out more about their loved ones, and enjoy more meaningful conversations with friends and family.
Psychologist Dr Madeleine Mason Roantree, working with the brand, said: "Many of us assume we know our loved ones better than we actually do. But research, and everyday experience, show us that we often have blind spots and gaps in our understanding of those around us."
The study also found many haven't asked key questions about themselves, with 40% unaware how they got their name. But 47% know how at least one of the Beckham kids got their names - with Brooklyn topping the list (37%).
However, not having the time to ask personal questions can lead to regret in later life - of those who've lost a parent, 30% wished they had asked about their grandparents.
And 27% longed to speak to them about their happiest memories. But while 57% want to know more about their loved ones, 21% don't know what to ask to get the conversation started.
The research also revealed train journeys were considered among the best ways to connect with others. This was due to the lack of distractions and increased quality time (59%), making the mode of transport the ideal environment for bonding.
Father and son duo George and Larry Lamb put National Rail's '36 Questions to Connect' to the test after admitting they rarely get time to really talk.
Larry said: "I'm so lucky to have a very close relationship with my kids but life's so busy, it's often hard to find the time to sit down and have a proper chat, connect, and have those more deep and meaningful conversations - but on the train you can.
"I really enjoyed playing 36 Questions to Connect with my son George, reminiscing on past experiences and sharing a few stories that we didn't know about each other. I didn't realise he didn't actually know what my first job was, and there's a few things I learnt about him too."
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