My Friends are Grandparents and with that--Title Changes

I just found out that my friends, Horace and Susan Smith are officially grandparents. Hooray! Welcome to the club. You have just been elevated and you didn't even have to campaign. Ain't that wonderful?

But now that you have First Grandbaby Lillian, that does pose a slight dilemma--what are your new official titles to add to your ever-burgeoning arsenal of titles?
Horace, you have so many titles, that when I first met you I asked you which one should I use? You replied that "Pastor" would suffice, so I call you pastor but refer to you affectionately as 'Bishop' (hey, do I owe you tithes for that?) lol. Susan--I call Susan but refer to her affectionately as 'Sister Smith'.
But there are many others titles. For instance, Dr. Smith, Professor, Doc, Pastor, Bishop, Presiding Bishop, Diocesan Bishop, Presiding Prelate, Daddy, Horatio (Susan, I betcha thought I'd forgotten), Dr. Horace E. Smith, II, M.D., Rev. Dr, Nephew, Uncle, Cousin, Brother, and Son--just to name a few. And not to be outdone, Susan also has quite a few titles of her own: Susan Davenport Smith, Pharmacist; Sister Smith, First Lady Susan, First Lady of the 14th District, First Lady of the P.A.of W., Niece, Auntie, Sister, Daughter, Wife, and Mommy--are some that easily come to mind.

So after years of encouraging, kissing, hugging and loving on practically every child in the near vacinity of the two of them, both personally and professionally; baptizing kids, and dedicating babies; and praying for and laying hands on children made vulnerable by poverty both nationally and internationally, Jesus has blessed them with a lovely granddaughter--First Grandbaby Lillian. Her mother is First Daughter, Lauren Smith Elrod.
Herein lies the dilemma of the new titles. Will the good doctor become 'PaPa', 'PawPaw', Grandpa, or Granddaddy? Will Lady Susan be referred to as Nana, Granny, Grandma, Grandmother, or G.G. aka Gorgeous Granny?
A Rose by any other name would smell just as sweet and grandparents--whatever they are called by adorable grandchildren would be just as blessed.
Congratulations!
The Churchy One