Well, something to that effect, I should think. [<-- That's mostly for Harry's benefit. Sebastian's definitely much younger, there's no "think" about it, but appearance-wise he could maybe pass for a decade younger than Lucifer; he's not sure if that qualifies as far younger among humans.]
My point is, it is ridiculous to throw around descriptors like "old" merely because younger people happen to be present, don't you think?