Kevin Federline Shares Adorable Snapshot of His Six Children All Together: 'They're Getting So Big!'

Kevin Federline's cute kids are growing up fast!

The former rapper took to Instagram on Monday to post a smiling snapshot of his six children, lined up from oldest to youngest (and, coincidentally, by height).

"2017 squad!!! They're getting so big," Federline, 38, captioned the pic. "Grandma took this pic at Jordan's first bball game Saturday."

2017 squad!!! They're getting so big... Grandma took this pic at Jordan's first bball game Saturday. @crownv_16 #thefedz

A photo posted by Kevin Federline (@federline4real) on Jan 9, 2017 at 2:21pm PST

PHOTOS: Stars Share Pics of Their Cute Kids

On the far left are Federline's 14-year-old daughter, Kori Madison, and 12-year-old son, Kaleb Michael, from his relationship with his ex-fianc��e, actress Shar Jackson.

In the center are sons Sean Preston, 11, and Jayden James, 10, with ex-wife Britney Spears.

At the end of the line-up are his daughters -- 5-year-old Jordan Kay and 2-year-old Peyton Marie -- with wife Victoria Prince.

In February 2016, Prince shared another group photo of her husband standing with his six kids while they all posed with red Xs on the back of their hands, in recognition of Shine a Light on Slavery Day, aimed at raising awareness about and stopping slavery and human trafficking.

We are raising awareness for #FREEDOM on SHINE A LIGHT ON SLAVERY DAY and wearing a ��� because we are in it to END IT!!!! We are supporting the #ENDITMOVEMENT, a coalition of the leading organizations in the world in the fight for freedom to end SLAVERY and HUMAN TRAFFICKING.... Join us in the fight by visiting enditmovement.com and help us raise awareness for all of the innocent victims across the world who need our help... You CAN make a difference and help save a CHILDS LIFE! ���������. ��� 27,000,000 people trapped in slavery around the world today. ��� Slavery is the 2nd largest global organized crime, generating 0.2 BILLION per year. ��� 55% of forced labor victims are women and girls. ��� Nearly 1 in 5 victims of slavery is a child. The average age a teen enters the sex trade in the US is 12-14 years old. ��� In 2013, the National Human trafficking hotline received reports of human trafficking in 50 US states. ��� An estimated 199,000 incidents of sexual exploitation of minors occur each year in the United States. That's one incident every 3 minutes!!! ���������������������������������������������

A photo posted by Victoria (@crownv_16) on Feb 25, 2016 at 8:46pm PST

WATCH: Kevin Federline Talks 'Overwhelming' Marriage to Britney Spears

Back in June, Federline sat down for an interview with VLAD TV, where he opened up about his "overwhelming" marriage to Spears -- who is currently in a rumored relationship with dancer Sam Asghari, who appeared with the singer in the music video for her song "Slumber Party" in November.

Federline got candid about his failed marriage to Spears -- which lasted from 2004 to 2007 -- and admitted "things didn't work out the way that they were supposed to." Check out the video below to hear more.