If we notice the age discrepancy after the first day, is there a way to see how old our sims are? I can see in my test that one of my sims has 8 days left till aging, and one has 7. Or I suppose if the game starts at 8am on Sunday (at least I think that's how sims 3 worked, not sure about 4), I could calculate how many days it's been and then see when 11 days would end.. Or else I suppose if they are different ages, at the start of the game it's not possible that one sim was less than 0 age (or seems unlikely), but it is possible for the other sim to have started at 1 day old, so a full young adulthood should be based on the younger sim's age, I would think?
Sorry, does this line of thought make sense?