Britney Spears' Birthday Post for Sister Jamie Lynn Features One of Her Famous Exes

Britney Spears is celebrating her sister Jamie Lynn on her birthday!

The 39-year-old Glory pop star posted a sweet tribute to her sister on Instagram and wished Jamie a happy belated birthday.

“Happy belated birthday to this beautiful soul 🎂🎂🎂 !!!” she wrote in the caption. “I love you so much and damn it I wish I was as smart as you at 30 !!!! It’s weird to say that I was basically your momma when you were younger and yes I’m still older but your soul is and always has been wise !!!!”

She continued, “I’m truly and genuinely inspired by your path and the life you have created for your beautiful children and I’m so f–king proud to call someone as beautiful inside as you my sister !!!!”

Britney added that she’s impressed by Jamie‘s physical strength as well.

“And not only are you a beautiful soul you’re so DAMN STRONG,” she wrote. “I was extremely taken back and still am to this very day !!! We play wrestled at home (such classy Southern chicks)… and you put me to the floor in literally two seconds after I gave all my might 😜😜😜😹😹😹 … I’ll never forget it !!!”

Click inside to see which famous ex was featured in the post…

Fans were somewhat confused about the photo Britney chose to accompany her tribute, a throwback pic which features her younger sister in glasses, sitting next to Britney and her ex-boyfriend Justin Timberlake.

“What a strange picture to choose,” one fan wrote, while another commented, “Not Justin,” along with a skull emoji.

Back in February, Justin issued an apology to Britney for his treatment of the singer after their breakup.