Britney Spears Poses With Teenage Sons in Rare Photo Together

Britney Spears can't believe how fast her boys are growing up! The "...Baby One More Time" singer, 39, shared a rare photo with her two sons, Jayden, 14, and Sean Preston, 15, as she marveled at how fast time has been moving since she welcomed the pair with ex-husband Kevin Federline. Posing with the teens in a warmly-edited photo from a recent outdoor expedition, Spears wrote in her caption, "It's so crazy how time flies .... My boys are so big now!!!!"

"I know … I know … it's very hard for any mama especially a mama with boys seeing them grow up so fast !!!! Talk about enough to make you go to your knees ... GEEZ !!!!" the Grammy-winner continued. "I'm extremely lucky because my two babies are such gentleman (sic) and so kind that I must have done something right !!!!"

Spears added that she has been keeping her sons off her Instagram for a while now because she wants them to be able to share their own identities. "I haven't posted pictures of them for some time cause they're at the age where they want to express their own identities and I totally get it," she said, adding that her boys "finally" allowed her to post this picture together after she went out of her way "to make this cool edit" of the sky and mountains behind them. "Now I don't feel left out anymore and I'm gonna go celebrate," she added with several crying laughing emojis before joking, "Oh s— I guess cool moms don't do that ... Ok I'll just read a book instead!!!!"

The last time Spears posted about her sons was last September when she shared just how excited she was for their upcoming birthdays. "My two lil men's birthdays are this week !!!!!!" she wrote on Instagram at the time, alongside a photo of a red sky with the moon and flowers. "You guys are getting older and so big and are waaay cooler than me !!!!! I love you both to the moon and back ….. and I hope all of your bday wishes come true and more !!!!!"

The "Toxic" singer is currently in the middle of a conservatorship court battle in which she is fighting to have father Jamie Spears removed as her conservator. Last month, Framing Britney Spears, a New York Times documentary released on Hulu, brought renewed attention to Spears' treatment legally and culturally over the years and highlighted the #FreeBritney movement. Spears has yet to comment specifically on the documentary.