It sounds like you are not able to view shared videos from your brothers Shared Photo Stream. I recommend starting by closing all the running apps on the phone:
iOS: Force an app to close
Double-click the Home button.
Swipe left or right until you have located the app you wish to close.
Swipe the app up to close it.
Then reset your network settings and test the issue again:
Reset network settings by tapping Settings > General > Reset > Reset Network Settings. Note: This will reset all network settings including:
- previously connected Wi-Fi networks and passwords
- recently used Bluetooth accessories
- VPN and APN settings
From: iOS: Troubleshooting Wi-Fi networks and connections
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