The young midfielder made his England debut in last week's win against Moldova.
"He takes it in his stride," Jagielka said. "He's really enjoyed being with the [England] squad and that's what you love to see, especially with a young lad.
"He's had so much expectation chucked on his shoulders and had to deal with a couple of bad injuries.
"So as well as the plus points, there has been a lot of negativity in his career but he seems to have come through that really well.
"He is playing well for Everton and that is the reason he got called up and on Friday when he came on he gave us a little lift."
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