Heidi Klum and Seal's four children are so grown up in rare family reunion photo

Heidi Klum is having the time of her life in Italy, and has been sharing some incredible photos from her trip so far with fans on social media. 

The German supermodel has reunited with her entire family, spending quality time with oldest daughter Leni, 19, who has been living away from home in New York City this year. 

What's more, the notoriously private model took to Instagram on Monday night to share an incredibly rare photo of all four of her children, and it's safe to say, they've all grown up a lot! 

Heidi posted a picture of herself smiling while driving in the car with her kids, Leni, Henry, 17, Johan, 16, and Lou, 13. 

The star shares her children with ex-husband Seal, and they split their time between their mom and dad's homes in Los Angeles. 

It's safe to say that Heidi is more than happy to be back with all of her kids during the summer months, and captioned the picture: "Happiness" alongside a slew of love heart emojis. 

Heidi and her kids have also been joined by her husband Tom Kaulitz, who has featured in several holiday snaps too. 

© Instagram

The trip has been extra special for Heidi and Tom, as last week they celebrated their wedding anniversary while away. The model took the opportunity to pay tribute to her other half on social media on August 3, which marked four years since they tied the knot in a ceremony in Capri. 

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Heidi and Tom are still as much in love now as they were when they first got together. Back in September 2018, the mother-of-four told US Weekly that Tom was the "kindest, sweetest, most caring, loving person." 

© Instagram

She added: "I feel so lucky. I don't know when I was this happy the last time in my life. I mean, I am with my children, but with, you know, a man. He's absolutely wonderful." 

MORE: Seal discusses emotional moment he became 'overwhelmed' - and it involves his children 

SEE: Heidi Klum's daughter, Leni, 18, looks just like her mom in string bikini

Heidi loves nothing more than spending time with Tom and her kids, and has been incredibly open about the bittersweet transition she faced when her oldest moved out of the family home last year. 

© Vince Bucci

During an appearance on The Late Late Show with James Corden she discussed Leni moving away for college and went on to talk about how she's coping with her other three children getting older too. 

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She said the whole process is "hard," and it never really lets up. "First they have a car and they drive, and that's hard. Then they move across the country, and that’s harder. I'm like non-stop scared." 

© Instagram/Heidi Klum

Taking the conversation back to Leni, James asked how often Heidi calls her and she responded: "This weekend, I called every two hours and I'm like, why don't you just call me back, you know?" 

She continued: "Now I want the number of the roommate, so I can bug the roommate if she doesn’t pick up. And then I’m going to get the number from the neighbor so I can call them."

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