You know what I love, in contrast? How Jim Gordon calls every guy he likes (who is younger than him) "son". Even Batman on occasion, I think. Young newbie cops, Dick, Tim, Jason, Jason Bard even in Batgirl: Year One, I believe.
(Of course, it's not as common to call a girl you know "daughter" in the same way as "son" is, and calling a female cop a term of endearment could potentially be perceived as condescending or inappropriate. But he is also very kind, warm and encouraging to young women as well, Babs obviously, but Renee Montoya and Jamie Harper too.)
I don't think it's ever really been explored all that much in the comics, but I always like the fact that Commissioner Gordon is this kind, solid, dependable, fatherly figure in the lives of all the bat-folk.
I think I read a ficlet once where Dick is Robin and was out on his own and injured his leg a little bit, and needs to look after it sooner rather than later (though it's not very serious). So he sheepishly pops into Jim's office at the police station, and of course Jim gets out the first aid kit, helps him and sends him safely on his way. I find it really sweet that the Robins can have this alternative safe haven with Jim if they ever needed it.
(Which is one of the reasons why the first issue of Battle for the Cowl bugged me, because Nightwing just brushes off Jim's offer to talk. It seems kind of unnatural that Dick would be so closed off with someone who's known him since he was a kid, who was close with Batman, and who would readily comfort him. I mean, I know the secret identity issue always puts a barrier between Jim and most of the Bats, but after NML there is just no pretending that there isn't some love within those relationships.)