Justin Timberlake shows off Silas's latest milestone on Instagram

It still seems like Justin Timberlake and Jessica Biel became parents just yesterday, but the couple's little boy is growing up fast! The singer posted a picture on Instagram this week showing off 15-month-old Silas Randall and his latest milestone as the toddler-on-the-move gave his proud parents a run for their money.

In the snap Justin, 35, uploaded to Instagram, little Silas, who is already walking, can be seen wearing a cute shirt and shorts combo, topped off with a trendy trilby hat, while waving an American flag. The "Can't Stop The Feeling" singer wrote alongside it: "Happy 4th of July, America! – The Timberlakes."

TAP TO VIEW GALLERY Justin Timberlake proudly showed off his son on Instagram

Actress Jessica, 34, and Justin rarely post pictures of their son, and he recently opened up about respecting Silas' privacy until he is able to make a choice of his own.

Speaking on The Today Show, Justin explained: "You think about the next five years and the next five years after that, and you think about the fact that he just got here. He hasn't made any choices. He chooses eggs or bananas.

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"You think a lot about the lives that me and my wife lead, but I wonder what privacy's going to mean in 20 years. Those are the questions that enter my mind, for sure, but I think that's something you don't have control over."

Justin Timberlake holding his baby Silas Despite his own fame, Justin wants to respect Silas' privacy

Justin continued that he plans to teach Silas all about the ups and downs of fames, in order to allow his son to make an informed decision. He added: "The best thing I can do is try every day to give your kid perspective so they understand what it means and what it doesn't mean."

And it looks like Justin is learning from Silas just as much, after he revealed to US radio host Carson Daly that fatherhood "blows your mind", saying: "Every day is just watching them grasp onto something and learn something new… It's been an extremely humbling experience."

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