How to share a calendar
How do my wife and I share a calendar and contacts on our IPhones & IPads while keeping our separate Apple IDs?
iPad 2, iOS 9
Here is how to share a calendar.
Share iCloud calendars on iPhone - Apple Support
Contacts are shared one-by-one, not an entire account. Open Contacts, and at the bottom of the details for each specific contact to be shared, tap “Share Contact”.