Joe hasn't called David yet. He knows he could. He's a friend after all. It would be just one of many birthday calls. Which is probably the reason why he hasn't called in the first place.
David knows that Joe's thinking of him today. He knows Joe will properly congratulate him the next time they meet.
And today they could only exchange a few words, and probably not even in private.
Joe doesn't know how David's celebrating. If there's a party, he's not invited, and if it's just family...
Joe can't help thinking about what he'd do today if it was just the two of them. He imagines how he'd wake David up, what he'd prepare for breakfast, how he'd drag him back to bed...
It's so easy to picture such a life that Joe feels he'd only have to reach out to touch it. But he can't because David has a life and a family and he's not part of that.
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