Firmware not updating to latest version
I used to have an s4 that went through many firmware updates, the latest of which installed kids mode.
I then broke that phone, and had to replace it.
The replacement installed a couple of updates, but doesn't have kids mode.
So, I assume that I don't have the latest firmware.
The original phone was one provided as part of a contract with Vodafone; the second phone is one I bought from Amazon.
Question 1: how can I check what is the latest firmware for my phone?
Question 2: assuming I don't have the latest, what can I do about it?
Thanks in advance.
Info from 'about device' section:
Model number: GT-I9505
Android version: 4.4.2
Baseband version: I9505XXUFNB9