The glade protects its own...but what exactly constitutes as your own?! It's time for a little clarity into a unique card interaction: Greenglade Caretaker and Barrier.
This stalwart guardian of the wood gains +2/+0 each time your ally gains Barrier. However, allegiances change at a rapid rate in Runeterra, so it's important to note that both the Caretaker and her Barrier-boosted allies must be in play for the buff to occur. That means on the board and ready to stand by all the glade holds dear.
After all, you never know when a wily opponent could steal your troops from your very hand.