The Kardashians star gave a glimpse into Amari Thompson's celebration on her Instagram Stories July 27, sharing a picture of large silver balloons that spelled out, "Happy Birthday Amari."
In an Instagram carousel, Khloe shared a selfie of her with Amari, who wore a casual, off-white outfit for his 17th birthday festivities. The Good American founder also posted a larger family portrait featuring mom Kris Jenner; 5-year-old daughter True Thompson, who Khloe shares with Tristan; and 6-year-old niece Dream Kardashian, who her brother Rob Kardashian shares with Blac Chyna. Tristan, 32, wasn't pictured.
"Someone is 17 today!!!!" Khloe captioned the images. "Happy birthday sweet sweet Amari!!! We are all so blessed to have been touched by an angel such as you. you are truly one of Gods greatest treasures."
"I'm grateful that I'm strong enough and brave enough to be a support system for someone else that has no other support system right now," said Khloe, who also shares 11 month-old son Tatum with Tristan. "You don't have to treat me right for me to treat you right—it's not the way I was raised."
In the awake of Andrea's passing, Tristan became the legal guardian of Amari, who lives with epilepsy.
"Amari is 16, and he is severely disabled," Khloe shared in a confessional. "It's just really sad, because we don't know what he knows or doesn't know, cognitively."
However, Tristan's return to California with Amari became complicated after extreme rains caused his roof to cave in on his home. As a result, Khloe explained, "Tristan and Amari are staying at my house right now until his home gets fixed."
Despite her ups and downs with Tristan, Khloe noted that she would support him through this time.
"I just think this is what family does when s--t hits the fan," she added. "All you have is your family. And Tristan and I are family, and we're gonna be family for the rest of our lives."