A colleague who took 12 days of annual leave has returned.

In the morning, I specifically looked at him a few more times, waiting.
Normally, after a long holiday, shouldn’t he come in and proactively say, "Brothers, you’ve worked hard, taking such a long break, I really feel bad, thank you all for holding up"?
But no.
He put down his bag, opened his computer, and started working as if nothing happened.
I thought to myself, do young people these days not even understand these social courtesies? Paid annual leave is given by the company, it’s not owed to you, and you can’t even say "thank you"?
Just as I was thinking this, a buddy at the neighboring desk came over quietly and said, "Do you know why he didn’t say anything?"
"These 12 days of leave were made up from compensatory time off accumulated from overtime last year. The week before he left, he pulled three consecutive all-nighters. This morning, he came straight from the hospital after staying with a patient."
"He’s afraid that if he says thank you, he’ll start crying."