Hi my son and daughter both received ipad mini's years ago. Can they still be updated to the latest software for apple?

Whether or not you are able to update any iPad to a newer version of iOS/iPadOS will be dictated by the iPad model - and the currently installed version of iOS. You can find this information here:

Settings > General > About

Not sure which iPad you have? Identify your iPad model.

Here is a list of the highest version of iOS supported by the older models of iPad (for simplicity - “generations” are shortened to a number) that are restricted in their ability to be updated:

32-bit devices (obsolete)

iPad1 - iOS 5.1.1

iPad2, iPad3 and iPad mini1 - iOS 9.3.5 (WiFi Only models), iOS 9.3.6 (WiFi+Cellular)

iPad4 - iOS 10.3.3 (WiFi Only), iOS 10.3.4 (WiFi+Cellular)

64-bit devices

iPad Air1, iPad mini2 and iPad mini3 - iOS 12.5.7

iPad Air2, iPad mini4 - iPadOS 15.7.5

Newer models are all able to be updated to the current version, iPadOS 16.4.1

• iPad Pro (all models)
• iPad Air (3rd generation and later)
• iPad (5th generation and later)
• iPad mini (5th generation and later)

If your iPad is capable of update to a more recent version of iOS/iPadOS than is currently installed, these support pages outline both the available methods by which the update can be performed - and troubleshooting should you experience difficulties:

Update your iPhone, iPad or iPod touch – Apple Support

If you can't update or restore your iPhone, iPad or iPod touch – Apple Support

If your iPhone, iPad or iPod touch won’t update - Apple Support

iOS update and restore errors – Apple Support

Be aware that while an iPad may be capable of update, in some circumstances you may need to use a computer to perform the update. To do so, you will need access to either a Windows PC (with iTunes for Windows installed) or a Mac (with iTunes or Finder - as appropriate for the installed version of macOS). Ensure that your installed version of iTunes has been updated to the most recent version; the essential device drivers are included.

Download and use iTunes for Windows – Apple Support

Update to the latest version of iTunes – Apple Support

Update software on iPhone, iPad or iPod touch in iTunes on PC - Apple Support

If you have a beta profile installed, ensure this has been removed from your iPad - as, otherwise, installation of production software updates may be inhibited. This support page provides the necessary information to remove the beta from your iPad:

How to uninstall iOS beta software - Apple Support

You should note that for your iPad to install an available update, its battery must be charged to at least 50% capacity - and/or be connected to its Power Adapter. Similarly, the iPad can only be updated over a standard WiFi connection - or be updated by a PC or Mac using iTunes or Finder - over a USB connection.

Older models may have no value for trade-in, but can be recycled for free:

Apple Trade In - Apple

Hello,

There are different ways to ensure the highest iOS that your device will support is installed on your device.

This support article has instructions about updating an iPhone or iPad wirelessly --> Update your iPhone or iPad - Apple Support

You can also use Mac and PC computers to update system software:

Update iPadOS - Apple Support

Use this support article to identify your iPad model --> Identify your iPad model - Apple Support and then the list below to find out what your iPad is capable of running. Alternatively --and somewhat easier-- is to simply try updating it and see if it will update. When updating, your device will update to the highest version currently available that it will support, or it will just say it is up to date (and can't go any higher) and won't install anything. Apple indicates ( Unable to update my iPhone 6 Plus from 12… - Apple Community ) I need to point out the obvious and state that if you want to run a higher system version than your current device will run, that you need to buy a newer device.

Here's a list of iPad models and the iOS/iPadOS versions they are capable of running:

iPad1 will only update to iOS 5.1.1

iPad2, iPad3 and iPad mini1 will only update to iOS 9.3.5 (WiFi only models) or iOS 9.3.6 (WiFi & cellular)

iPad4 will only update to iOS 10.3.3 (WiFi only) or iOS 10.3.4 (WiFi & cellular)

iPad Air1, iPad mini2 and iPad mini3 will only update to iOS 12.5.7

iPad Air2, iPad mini4 will only update to iPadOS 15.7.5

These models are all able to be updated to the current version, iPadOS 16.4

iPad Pro

iPad Air 3rd generation and later

iPad (5th generation and later)

iPad mini (5th generation and later)

You are asking two somewhat unrelated questions.

To get more information about the Apple Trade In service click on the link --> Apple Trade In - Apple