find my phone

Hello, i set up my family sharing account. I have an iphone 4,4s,5 and an ipad. my daughter is on my family sharing account and i can see her on all of my devices except my iphone 5 in the find my iphone app? any ideas as to why this could be happening? obviously all the other devices including her 4 is set up as they all work correctly but its only the 5, the one i use most often that wont show her location.

Thanks for any ideas Todd