Hi Gary!  Congrats on the new addition!

I would highly recommend doing gradual introductions.  Bring the kitten home
and put it in a bathroom or spare bedroom with all the necessary items
(litter box, food etc).  Your resident cats will get to know the new one
under the door.  If they seem interested and not aggressive, introduce the
little one to them, giving them praise and treats.  Making the kitten a good
thing.  Ignore the kitten as much as possible.

If they are grumpy, you'll need to do extended introductions, leaving the
kitten in the room for a couple of days to a week until your resident cats
get used to the idea.  Don't yell at them for being upset.  Tell them
quietly no, and explain to them the kitten needed a new home and older
siblings to help it.  Pat them and give them lots of love and attention
until they come to accept the new one.  There are a lot of website help on
extended introductions.  Google introducing a new kitten.