In an interview with Naga Munchetty for BBC Radio 5 Live, Sophie said that she and her husband Prince Edward are "protective" of their firstborn, but that they also have to let her live her own life.
When asked why Louise, 17, isn't on social media, Sophie said: "Purely her choice. Absolutely. I wouldn't deny her going onto it. But she's not really that interested in it. There's a few platforms that she talks to her friends on. But that's basically it. She doesn't put anything out about herself at all. She's very private. She's got her eyes fairly wide open."
WATCH: Sophie Wessex wells up as she remembers Prince Philip
The Countess added: "But inevitably there will be moments that, you know, may not go so well for her. I just hope we can be there to support her through those moments. I would hope that she can go on with her studies, which I think she probably will want to do, and I hope that she and her friends will protect her from anything that somebody might want to do.
"But I have to let her live her life. It's not mine to live. I can only equip her the best that I can, and then she has to make her own choices. But I hope for the next few years, at least, she will still be able to be as private as she wants to be."
Sophie spoke to Naga Munchetty for BBC Radio 5 Live
The mother-of-two also shares a 13-year-old son James with her husband. Sophie quipped that teachers and fellow parents at his school are more used to seeing her in gym attire than formalwear. "Generally speaking, we have a pretty good private life," she said. "You know, we behave very normally when it comes to children's schools and everything.
"I was joking with my son's school on Friday, because we went and opened their new pre-prep department in music school, and I was walking in in a dress. They are more used to me walking in in my gym kit frankly. So it was quite funny suddenly being there in a more formal role. I think it's about how you want to be perceived. And if you set that tone earlier on, then generally people respond like for like."
Prince Edward and Sophie also share a son, James
The Queen's daughter-in-law, who shares a very close bond with Her Majesty, also reflected on the increased awareness around the Wessex family, particularly after Prince Harry and Meghan stepped back from royal life and relocated to the US. Sophie said it could only be a positive to have the spotlight shone on causes close to her heart, such as her work with conflict-related sexual violence.
"That can only be a good thing," she mused. "Because it means that more people will take an interest in what I'm doing, on an official basis, and therefore the organisations that I work with, by default, should receive more attention. So that cannot be a bad thing."
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