NCIS: Los Angeles' Sam Hanna has a larger family than previously thought.

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In addition to his daughter (or daughters, depending on which episode you watch), it appears the former Navy SEAL also has a son.

Named Isaac, the teenager will appear in the series' Christmas episode, according to TV Line.

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If you are wondering where the youngster has been hiding for the last five and half years, NCIS: LA is prepared with an answer. Like his father, the teen appears to be interested joining the armed forces and spends most of his time at military school.

Sam (LL Cool J) is notoriously quiet about his domestic life, so the idea that he has a secret son is not entirely unbelievable. The longest viewers have engaged with Sam's family was when his wife, Michelle (Aunjanue Ellis), helped the team take down Siderov. It remains to be seen if she will return as well.

Titled "Humbug," the Christmas-themed episode was penned by Andrew Bartels and will be directed by Kyle Harimoto. "Humbug" air on Dec. 15.

NCIS: LA airs Mondays at 10 p.m. ET on CBS. Click the video below to see a preview for the series next episode.