The MTV reality star shared a slew of gorgeous images of her little man to Instagram today, marking twelve months since his arrival in the world.
An emotional Jenelle said: "It's officially Kaiser's first birthday today! Time has flown by so quickly and soon enough you aren't going to be my baby anymore! #Bittersweet."
Kaiser's dad is Jenelle's partner Nathan Griffith.
Jenelle is also mum to son Jace, four. Her pregnancy with Jace and life as a single mum was featured in the MTV show Teen Mom.
The reality star - who is training to become a medical assistant - became engaged to Nathan in January. They later separated for a few months before reuniting.
She told OKMagazine.com last week: "We're working things out currently. We took a break for about four months. During those four months I just focused on myself, took care of Kaiser, spent time with Jace on the weekends. No matter how depressed I was, I didn't let our breakup effect my schooling. I usually would in the past. I'm proud that I was able to stick to it."
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