my granddaughter calls her mother and father poppa and momma, I am Nana Helen, (to my granddaughter, and to my d-i-l's 12 year old son.)

EDIT: Dr bill, in the kindest way, made me into a slouch for not taking the effort to look things up... Thank you..
my D-I-L's mother is known my a tagalog word for grandmother, lola (ok, i was too lazy to look it up, Dr Bill provided it to me!) --i don't know what by what name the children call her father.(since he is australian, (born in Scotland), i suspect its is one of the common grandfather/pa variations. )

My honorary grandson calls his grandparents (fathers side) as grandma, and grandpa(with their name's attached...(as does my granddaughter (who is, of course, no blood relation to them!)

My ex is also grandpa, Grandpa Jimmy. (and his wife, is grandma Irene!)
(the kid's make out like bandits: D-I-L has 2 parents, her son has 4 (blood relative) grandparents, and 3 'honorary' ones. My granddaughter has 4 (blood relative grandparents) and 3 honorary ones. (and there are 3 great parents alive, unfortunately, my parents have no relationship with me, my kids, or their great granddauther, and my ex's mother is infirm, and semi senile.)

like the 'coming demographic change', there are more older generation members of the family than younger! (and grandparents are spread out. one currently lives in Singapore, one SF,CA, 2 north of SF, 3 in NYC.)