Cheers for the replies MrsBexie, LimeSlice and Nai
I do think that my sis has amenorrhea but I am not going to diagnose her! I've told my sis to get to the doc sooner than 2 wks cause her body could get back on track and she could have an oopsie! (Even tho my sis would love to give her 8yo boy a sibling, her DH is not keen on the idea at all!)

I was trying to do the math on how late she could be as she hasnt replied to my message last night asking the question and I thought maybe if she has just gone over being late then a positive HPT might not be possible, but I THINK she is around 6 weeks from her last AF so a HPT would definitely have a result. It was wishful thinking last night that she was pg was I would LOVE to be pg with my sis and we would be due about the same time!!

I will be seeing my sis this weekend I hope so will be having a talk to her. She is pretty clueless with this sort of stuff!!

Thanks again gals