Considering its probably been a little over a year at the most since she died (they were only in SAO for 2 years), seeing him with a wife and kid (especially a kid that old) is probably something of a shock regardless.
If I am not mistaken, that kind of headpiece is generally used to depict ghosts.
It is. Just not the swirl on it.
Yui-chan!kyah!*lovey-dovey*Do your best, Kirito-kun! ♥*float*I'll bring you a lot of fishes!!Daddy's leaving, come see him off!*pat*kyah!Ghost girl Sachi's wanderingHE... HE LOOKS SO HAPPY...!!Okaaay!I thought that Kirito would be sad, all alone*float*So at last I've decided to go see himHis house should be around here...With wife and child!?The afterlife...Daddy! Have a nice day!