[matese]

Well the big day has finally arrived, you must be ecstatic. Your older baby may not take to the bouncing baby with teeth like a shark right off the bat. 1-puppies do not smell like a "dog" they have a baby smell to them, this usually scares the one time "only child"
2-puppies bouncing in older dogs face is not a pleasant experience for your older baby.
Your older baby will need a "safe haven" away from this zooming fluff ball. My girls always stayed on the sofa "high grounds" when a new kid came home. Your older baby will do just fine once he gets adjusted to "this kid is NOT leaving".
Do NOT force your older one on the new kid, let him check out this ball of energy on his time, his terms. You will soon see your older one spending more time on the ground, sniffing the baby, and soon they will be romping and wrestling, and will be BFF.
I am soooo excited for you, you will have much fun and laughter with two precious babies.