Sienna Miller has admitted that she initially struggled with the age between herself and her boyfriend Oli Green and 'didn't expect' their relationship to become so serious as a result.
The LA-based actor, 27, might be 15 years Sienna's junior but she has revealed that he is more respectful than men of her own generation.
The Golden Globe-nominated actress, 42, who welcomed a daughter with Oli in January, praised Oli as 'wise and well-adjusted'.
In an interview with Harpers Bazaar magazine, Sienna, who met her toyboy lover at a Halloween party in 2021, said: 'I didn't expect to take it seriously and then quite quickly, I fell in love.
'I wasn't like, "I'm gonna get a younger boyfriend." It was more, "F*ck! Why are you young? That's so annoying."'
![Sienna Miller, 42, has admitted she initially struggled with the age between herself and her boyfriend Oli Green, 27, and 'didn't expect' their relationship to become so serious as a result](https://i.dailymail.co.uk/1s/2024/06/11/17/85977573-13518607-Making_rare_comments_about_her_fiercely_private_relationship_she-a-1_1718123413854.jpg)
Sienna Miller, 42, has admitted she initially struggled with the age between herself and her boyfriend Oli Green, 27, and 'didn't expect' their relationship to become so serious as a result
![For the cover she wowed in a gold sequin mini dress with a Gucci belt as she fixed the camera with a sultry stare](https://i.dailymail.co.uk/1s/2024/06/11/17/85977583-13518607-For_the_cover_she_wowed_in_a_gold_sequin_mini_dress_with_a_Gucci-a-2_1718123425620.jpg)
For the cover she wowed in a gold sequin mini dress with a Gucci belt as she fixed the camera with a sultry stare
![The Golden Globe-nominated actress, who welcomed a daughter with Oli in January, praised him as 'wise and well-adjusted' (both pictured in Cannes in May)](https://i.dailymail.co.uk/1s/2024/06/11/17/85978659-13518607-The_actress_42_and_Oli_27_were_first_linked_in_February_2022_and-a-3_1718124570186.jpg)
The Golden Globe-nominated actress, who welcomed a daughter with Oli in January, praised him as 'wise and well-adjusted' (both pictured in Cannes in May)
Sienna continued: 'There is a difference in the way that generation of men respect women. It's specific to him, he is very wise and well-adjusted, but I do believe it's also that generation.
'They have grown up with a slightly more level playing field. I see it in his female friends as well as in the men.'
Sienna also told the publication how she is 'heaven' since welcoming her second daughter, whose name she has yet to publicly announce, and that the experience has been both 'healing' and 'cathartic.'
Sienna said of her new daughter: 'She's magical. It's amazing when you have these little people and there's a universe inside their heads. Her father is incredibly bright, but also very deep.
'And she's straddling this kind of comedy-jokester part of me and this intensity that comes from his brilliant mind.'
Meanwhile, the star, who has a sell-out clothing range with Marks and Spencer, addressed working in a male-dominated industry through the nineties.
Sienna said: 'She used to talk herself into different shapes to make men feel more comfortable.
![Sienna also said she is 'heaven' since welcoming her second daughter, whose name she has yet to publicly announce, and that the experience has been 'healing' and 'cathartic'](https://i.dailymail.co.uk/1s/2024/06/11/17/85977571-13518607-Sienna_Miller_gushed_over_her_younger_boyfriend_Oli_Green_and_re-a-12_1718125092695.jpg)
Sienna also said she is 'heaven' since welcoming her second daughter, whose name she has yet to publicly announce, and that the experience has been 'healing' and 'cathartic'
![She spoke about her joy at working with Kevin Costner on Western saga Horizon, describing the actor, 69, as her 'first love'](https://i.dailymail.co.uk/1s/2024/06/11/17/85977575-13518607-Another_look_saw_her_slip_into_a_silky_orange_shirt_which_was_bu-a-10_1718124831660.jpg)
She spoke about her joy at working with Kevin Costner on Western saga Horizon, describing the actor, 69, as her 'first love'
![Sienna is undergoing a renaissance with fans and commentators are declaring that the British actress has 'never looked better' despite the demands of work and having a young family](https://i.dailymail.co.uk/1s/2024/06/11/18/85977585-13518607-Another_radiant_black_and_white_shot_showed_her_modelling_a_pret-a-24_1718125308216.jpg)
Sienna is undergoing a renaissance with fans and commentators are declaring that the British actress has 'never looked better' despite the demands of work and having a young family
'It was a slightly belittling time. I could talk myself into all sorts of shapes to make the men in the room feel comfortable. And God forbid that you offend a man's ego by rejecting them.
'It's interesting, being older now, and having been raised in that moment, learning from people who are younger about how clear they are in their boundaries, having that self-assuredness and self-advocacy, having "no" in the repertoire in a way that we just weren't encouraged to have.
'I feel much more balanced and settled and wise. I think I've got some wisdom from all of the things I've been through. The more interesting and complicated your life is, the better you'll end up being.'
Sienna appears in Kevin Costner's latest Western Saga Horizon which received a 10-minute standing ovation at Cannes Film Festival in May.
Revealing her surprise when the Hollywood A-Lister wanted to work with her, she said: 'Kevin sent me the four scripts, and they were astounding.
'Then he asked to Zoom, and I was thinking, "Be still my Nineties heart!" because I had been obsessed with Kevin Costner growing up.
'He was my first love. At the end he said, "Sienna, I have one question for you: will you go West with me?" I died. I said, "I would go to Mars and back with you, Kevin."'
Sienna is undergoing a renaissance with fans and commentators are declaring that the British actress has 'never looked better' despite the demands of work and having a young family.
![As well as the five-month-old she shares with Oli, Sienna has daughter Marlowe, 11, with her ex partner Tom Sturridge (pictured: Sienna, Marlowe, and Oli in Cannes in May)](https://i.dailymail.co.uk/1s/2024/06/11/17/85978787-13518607-As_well_as_the_five_month_old_she_shares_with_Oli_she_has_daught-a-11_1718124836855.jpg)
As well as the five-month-old she shares with Oli, Sienna has daughter Marlowe, 11, with her ex partner Tom Sturridge (pictured: Sienna, Marlowe, and Oli in Cannes in May)
Brand and Culture Expert Nick Ede told MailOnline that he predicts that Sienna could be about to 'steal the crown to become the UK's biggest Hollywood star'.
He said: 'Sienna's been looking after herself and got herself red carpet ready knowing this is going to be her big return to the big screen and knowing all eyes will be on her.
'She's done everything right and she commands The Croisette - the beating heart of Cannes.'
The July/August issue of Harper's Bazaar UK is on sale from June 13.