Ian comes back changed.

here's what Emmy Rossum (who plays Fiona, Ian's sister on Shameless) said about Ian Gallagher coming back and how much he has changed.

TVLINE | And Ian enlisted at the end of last season. Does that mean we won’t be seeing him?"No, he’s back. He’s just back later in the season. That’s a fascinating arc because he’s been away for a couple of episodes, and the changes that have happened in him are pretty drastic." (source)

we already know, as Emmy said, that he will come back and act like his mother, Monica.

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