I put a LOT of thought into how the meeting of brothers should go down, and while it probably wasn't necessary, it went down perfectly.
Basically, we wanted to heed off as much jealousy as we could, so Jacob actually wasn't in the room when Cooper got there. Once he got there, we called the nursery and asked that they bring baby brother in about five minutes. My parents brought him to the hospital, and Jimmy actually met them at the door to the baby wing to get Cooper, while my parents stayed in the waiting room.
Cooper really loves balloons right now, so he brought a baby boy one as well as Spider-Man.
Once he got in the room, he gave me the balloons and we let him take in that mommy was in the bed, had a boo boo on her tummy and couldn't get up. He was already asking about his baby brother (He called him "Dannel" which was good since we knew that was the middle name but still nothing on a first name!) and squealed when the nurse brought his brother into the room.
I think they were immediately best friends <3
Cooper, of course, wanted to hold his little brother, so after a quick lecture about being VERY careful and loading up the chair with pillows, Jimmy handed him over and stayed right by his side, of course.
It only lasted a few minutes (toddlers and their attention spans) so we went ahead and told my parents to come back. Cooper went back and forth wanting to hold his brother and play.
They boys also exchanged presents - Cooper got the baby a little monkey toy/lovey, while JD gave his big brother an Avengers shirt.
When it came time for big brother to leave, we actually had JD leave the room first so it wasn't as obvious that Cooper was leaving and JD was staying.
As you can see, Cooper was (and continues to be) totally in love with his little brother. Their first meeting melted my heart!