I think it's an Irish idiom-type thing--"it's himself" (affectionate and slightly exaggerated importance over a simple "him"). Transposed over to more than one person = "themselves." There's your linguistics lesson for today.
M60 H52 D20 M14 yrs OW-old gf from 1986 bomb-5/18/08 H filed for D-9/10/08 D final 4/24/09 xH remarried (not OW) 2012
