If you mean Kendall's sister , Katie, then the answer is 14 (currently).
Katie is played by Ciara Bravo, who was born on 18/03/'97.
The boys from big time rush are in their early 20s
Carlos Pena from big time rush is 22 in 2012
Ciara bravo plays Kadie Knight in big time rush and is 9 years old
21
He is 21
he is 21 years old.
no and they are in ther 20s
31
No,they are very young.
10
13
he is 46