I haven't played long enough with Chachan to consider birthdays and such, but I would probably age him up based on RL time, unless something major in-game happened. I just hope he's grown as a character enough to reflect that as well!
For everything else, I try to keep things relatively fluid just due to the nature of so many characters doing so many things. How quickly time passes is left to the narrative, though I tend to refer to events that occurred the previous real days as "last sun" just for simplicity's sake. Plus I've been bad at keeping notes on everything Chachan's been doing, so trying to keep tabs on how many suns he's spent in transit from point A to point B would probably get lost in the mix.
(Thank god for Aetherite being an IC thing...)
For everything else, I try to keep things relatively fluid just due to the nature of so many characters doing so many things. How quickly time passes is left to the narrative, though I tend to refer to events that occurred the previous real days as "last sun" just for simplicity's sake. Plus I've been bad at keeping notes on everything Chachan's been doing, so trying to keep tabs on how many suns he's spent in transit from point A to point B would probably get lost in the mix.
(Thank god for Aetherite being an IC thing...)