Scarlett Johansson's daughter is ''obsessed'' with Colin Jost.

The 35-year-old actress has five-year-old daughter Rose with her ex-husband Romain Dauriac, and sources have now claimed the tot has taken a shine to her mother's new partner Colin, whom the 'Black Widow' star got engaged to in May.

A source told Us Weekly magazine: ''Colin is a great father figure for Rose. He loves playing with her and she is obsessed with him.''

Meanwhile, Scarlett - who has also previously been married to Ryan Reynolds - recently said she used to ''romanticise'' marriage, and didn't fully ''understand'' the process in her two previous marriages.

She said: ''The first time I got married I was 23 years old. I didn't really have an understanding of marriage. Maybe I kind of romanticised it, I think, in a way.''

And the 'Lucy' star has said she is now able to make ''more active choices'' about her love life, and has a greater desire to ''build a family'' than she did when she was younger.

She added: ''It's a different part of my life now. I feel like I'm in a place in my life, I feel I'm able to make more active choices. I'm more present, I think, than I've been before.

''The idea of building a family, making a family, and having that work, I like that idea. I think that would be wonderful. I've always wanted that. I wanted that also in my marriage to my daughter's father as well. It just wasn't the right person. But I like that idea.''

Scarlett and Colin got engaged in May after two years of dating, and the actress said she was ''surprised'' by the proposal.

The 'Marriage Story' star said: ''It was surprising, he's got a lot behind that news desk he's hiding. He's very charming and very thoughtful and romantic. But yeah, I was surprised. Even if you kind of imagine what that moment's gonna be like, it's still beautiful moment. It was very personal, it was a very special moment. I think, more than anything, when someone tells you they want to spend their life with you, that's a lovely, special thing.''