HOW DO I SET UP FAMILY SHARING ON IPHONE 4?
HOW DO I SET UP FAMILY SHARING IN ICLOUD ON AN IPHONE 4?
iPhone 4, iOS 7.1.2
According to the quote below from Set up Family Sharing - Apple Support you would need iOS 8 and unfortunately that is't possible on an iPhone 4:
Here's what you'll need to set up Family Sharing:
- An Apple ID signed in to iCloud and iTunes
- iPhone, iPad, or iPod touch with iOS 8 or Mac with OS X Yosemite