Needing a little bit of advice or a cute idea

Hello, my husband and I have been throwing out ideas and who we want to be a children's godparents we currently have a 4 year old and another boy arriving in the next month or so....

And we finally picked the two Perfect People..

My brother his Pure Heart is the friendliest giant you will ever meet lol (he is 6' 7") it's never afraid to take on a challenge and always willing to learn something new and we definitely think that would be a huge Plus for children to learn. And if we depart before our time and our children are grown hopefully his can-do attitude will rub on them.

And last but not least my dear sister, which she has had more than her fair share of Trials. She is one of the sweetest people you would ever meet she would give you the shirt off her back and her last dollar I and just simply asked for a handshake and for a smile... recently she has been diagnosed with Cushing's disease at the age of 21.... and she will no longer have the capability of having her own children... she loves and adores our 4 year old ( and he loves his autie) and she has been kind of living through my now pregnancy because it's something she will miss out on...

And for Christmas this year we would like to ask them to be our godparents. Our four year has made them each Christmas card and we wanting to slip in a little note or poem asking from his point of view if they would be his grandparents and soon to be little brother's..

We are really open for ideas for this is a very emotional topic as well as a hardship our family has a been through in the last year we are hoping to write it down and have each of them read their own... so I'm not a blubbering ball baby asking