Kate Hudson Celebrates Son Ryder's 16th Birthday with Touching Throwback Video

Kate Hudson has a few sweet words for her teenage son on his 16th birthday.

The 40-year-old actress celebrated Ryder Russell‘s big milestone with a sweet tribute post shared on her Instagram Tuesday. Alongside a throwback home video of her son on his second birthday, Hudson also penned a heartwarming message to her eldest child.

“I didn’t realize it would be here so fast!” she began. “16 years today. 16. I will savor these next couple years before he flies the nest.”

“People sometimes get sad on days like this. Time creeps up on us and rocks us a bit, reminding us that the years don’t wait for us to be ready. Well, RYDER IF YOUR READING! I’M READY!!!” she continued.

Hudson went on to gush about Ryder’s growth and her excitement for the teen’s bright future.

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“I’m excited for your future. An amazing young man you are,” she wrote. “I am honored that you chose me to be your mother.”

The Almost Famous star ended her touching message with a joke, writing, “And here’s the thing…you still have two years under this roof. My roof, my rules 😉 Happy Birthday baby @mr.ryderrobinson.”

Hudson also documented Ryder’s birthday on her Instagram Story, though her son was slightly embarrassed by all the attention he was receiving from his famous mom.

“Look at the birthday boy! How’s 16 treating you?” she asked.

To which he jokingly replied, “It was great until you started filming me.”

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Hudson was married to Ryder’s father, The Black Crowes frontman Chris Robinson, from 2000 to 2007. When they divorced, the couple agreed to share custody of their child.

Hudson opened up about what it was like raising Ryder in 2016, telling PEOPLE at the time that her son is “a great kid.”

“It’s a beautiful time,” she said of his preteen years. “I feel like seeing him now is the most amazing thing because you’re really starting to understand and see their character as they get to this age.”

The How to Lose a Guy in 10 Days star also spoke about Ryder in December, revealing on The Rachael Ray Show that her oldest child “doesn’t care” about getting his driver’s license despite being of legal age to apply for a learner’s permit.

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“The second I was 15, I was like, ‘Give me my permit!’ ” Hudson recalled. “Ryder’s kinda like, ‘I got basketball practice, I can’t really do the permit thing right [now].’ “

In addition to Ryder, Hudson is mother to son Bingham “Bing” Hawn, 8, with ex-partner Matt Bellamy. The duo announced that they had called off their engagement in December 2014 after four years together.

The Golden Globe winner welcomed her third child, daughter Rani Rose, in October 2018 with boyfriend Danny Fujikawa.