Continuity mistake: At the end the little boy tells Gibbs the password he has chosen for his tree house. As he does, Gibbs is working on the railing at the opposite end to the ladder. Gibbs says it's a good password and to come up. However he is now at the end of the railing by the ladder. (00:39:50)
Continuity mistake: At the very end we see Gibbs working on the treehouse. As the little boy climbs the ladder, Gibbs is working on a railing. Camera changes and now he is stepped back from the railing. (00:42:00)
Continuity mistake: When DiNozzo is reading the ingredients of the brass stripper, he has 2 hands on the tin in one shot and just 1 hand in the next. (00:29:00)
Continuity mistake: When Ducky is pointing at the hairline fracture on the x-ray, he stops pointing. Camera changes angle and he is pointing again. (00:11:20)
Continuity mistake: When interviewing the girl at the crime scene, the blood splatter on her face keeps changes instantly. (00:03:30)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.