Heidi Klum and ex-husband Seal's son makes rare social media appearance on milestone day

Heidi Klum is currently on cloud nine as she marks a joyous family occasion even involving her ex-husband, musician Seal.

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The supermodel's youngest son, Johan, just turned 16, and his mom couldn't be more proud of how much he has grown.

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She took to Instagram with a throwback photograph of the teen as a young boy making a funny face while sitting in his mom's arms.

"Sweet 16 Today JOHAN. I LOVE YOU SOOOOO MUCH," she captioned her picture with a barrage of celebratory and heart emojis.

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Heidi and Seal are parents to three others, including eldest daughter Leni, 18, who is a model like her mom, and whose biological father is Flavio Briatore.

They also care for 17-year-old son Henry and daughter Lou, who recently turned 13, having developed an effective relationship as co-parents.

Heidi celebrated her son Johan's 16th birthday

Neither Heidi nor Seal often share photos of their offspring, making the snapshots they do post, all that more special.

On a recent appearance on The Late Late Show with James Corden, Heidi opened up about how challenging she's finding it watching her children growing up.

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The star discussed her eldest, Leni, moving away and went on to talk about how she's coping with her other three children getting older too. 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."

heidi klum with her family
heidi klum with her family

The supermodel and her musician ex are parents of four

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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