Time flies! Kailyn Lowry shared a beautiful new family portrait on July 9, and fans were immediately overwhelmed by how big her kids are getting! The Teen Mom 2 star posed on the beach with her three sons, Isaac Rivera, 8, Lincoln Marroquin, 4, and Lux Lowry, 11 months, and we can't get over how sweet the moment was.

"Great pic and the boys are getting so big," said one fan about the touching family portrait, captioned "my world" and taken by photographer Jon Lloyd Jr.. "Look at how big they are getting!! Very proud momma :)," agreed another. A third wrote, "They are getting so big!!! I remember seeing them as babies on the show. They grow so fast?."

Fans were particularly obsessed with Baby Lux, who is clearly developing quite the little personality. "Lux over here like straight model face ? YAAAAAAS," said one, while another wrote, "Lux is working it. ??" Of course, people were also excited to see what a handsome young man Isaac is becoming, too. "Not that all your bubs aren't beautiful BUT your oldest is just gorgeous, girl!" As for who looks most like Kail? Fans seem to think it's obvious. "Whoa [Kail] Issac is your little twin!!!" said a commenter.

It feels like just yesterday that Kail was welcoming her youngest son, and he's already almost one year old! Three days earlier, Kail posted an adorable photo tickling her baby boy on a trampoline with the caption, "The littlest one turned 11 months old today. I cannot believe he’s almost 1! Thankful for you, Lux Russell." We can't wait to watch these little guys keep growing into spunky little men.

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