Me, my sister, and my mom all shared a iCloud. I recently lost my phone in a car wreak and I lost some really important pictures. I lost my boyfriend in the wreak and I was trying to get my pictures back because of so.. but when I got my new phone and tried to sign in and get my pictures,notes, etc i got my moms instead. And everytime I try to reset it or try to do it again it always gives me my moms pictures and everything.. it says that there is 3 iPhones with data but won't let me get mine back?
First of all, sorry to hear that about your boyfriend!
What you might try, is resetting your phone and then plugging it in to your computer and then selecting "restore from backup". This might not give you the very latest photos but at least the ones until the last backup you did.
Hope you get them back!