"a granddaughter event" is not correct or usable in written English.
To make an example sentence using the correct phrase, you can say "My granddaughter's event was a great success."
"I'm thrilled to be at such a grand event.
(The Royal Caledonian Ball is a grand event of traditional Scottish dancing).
It was a grand event mired in deception, at least with respect to the drug situation.
A trip was a grand event, a reason to don gladrags and make a night of it.
"Unfortunately, the development of Azerbaijan, holding such a grand event as Eurovision, the arrival of many guests here, are perceived by some with jealousy," Mr. Abdullayev said.
Stanford, known more for its academic prowess than its football pedigree, was in rarefied air: Saturday's nationally televised game against No. 6 Oregon was seen by many as a grand event for the No. 3 Cardinal.
Here, South Korea has the advantage, given its hostile border, militant labor unions and experience as host of the Seoul Summer Olympics in 1988, a grander event than the 1998 Winter Games in Nagano, Japan.
"I am not just a wedding hall," he said, "but a spectacular grand event hall".
Only the singer seemed to have missed the memo that this was a pretty grand event.
Our opening ceremony (a customary grand event in this part of the world) may, hopefully, be the time to breathe a sigh of relief.
At the United States Open last year, Jankovic produced her best result in a Grand Slam event, losing in the final to Serena Williams in straight sets.
