I always thought my parents were bullet-proof. It’s a big shift in thinking to realise they are, indeed, mortal. I do think it’s better to dwell in the present when possible rather than focus on the end, although you may find you swing between the two.
Good to hear that the birthday party went well. I was cataloging photos (into photoshop) from when we went to Werribee Zoo a couple of years ago and was astonished again how much Finn has grown up in that time.