Clearing imigration in AMS our FWNA DC10 FA's were leading us through the passport guy when the British crew came up behind us, and said, " Nice of you to bring your Mum's along". Our FNWA Capt. promptly turned around to them and said,"when we are done ******* them we will **** yours too"! Suddenly followed by complete silence, and wide eyes, they didn't even respond and we cleared customs behind our Mums!