The second is that, while 29 hasn't been old since at least the 14th century, it is old enough to be aware that a whole other generation has sprung up behind you, and is likely, despite your best efforts, to be around after you are gone. Now I'm expendable. Everything I do with my life from this point, genetically speaking, is just gravy. To be sure, I'm thrilled to be becoming a father. But the whole point of children is that they survive beyond you.
Children are the best, most delightful admission of mortality there is.
My wife doesn't seem to worry about death all that much, but she also firmly believes in an afterlife of some sort or another. Since I don't believe in any afterlife, I think their assumptions are overly optimistic, but I stop short of saying they're nuts to believe what they do. The thing about death is that you just don't know. The funny thing about having contemplated death as much as I have recently is that it now bothers me a bit less. It still bugs me, of course.