Celebration could be anything. Celebrating a birth of a child, graduating college, and a job promotion.
Yes, this happened to me once. She said it's a birthday-it's the 9 of cups but sometimes she can tell if it's a birthday or a celebration. I think it was a 9 of cups in the Home card which is how she knew it was a family member or close friend's birthday, not my own, and not like a national celebration. It had a meetup and contact from an old love interest, who was a Knight of Wands (not the KoC who never showed up) and this happened exactly on the day of my mom's birthday. And yes there was a meetup-he actually had taken me out on a proper dinner on that day.
Curiously, I have another contact prediction that came in . She saw me going abroad-World-and soon after World, I'd hear from a guy with whom I wasn't in communication with, and the 2nd layout showed it's a Knight of Wands. I did travel abroad a month after she read for me back in December but I've been back for 4 months (I just came in as travel restrictions hit ).
Today, the old Knight of Wands-same guy as above-contacted my mom out of the blue. Now, the back story is that he and my mom were very friendly and she's the reason we met long long ago. And to answer a question from before, yes, parents can be shown as suits. My mom is 99% of the time the Empress but several times she's been shown a Queen of Swords but usually Yona can tell it's my mom.. She can touch a card and recognize the energy. This Knight of Wands has been shown many times with a link to my mom. Communication was shown as remote-2 of pentacles. which is true, he texted my mom. So when Yona saw this, I did say either it's him texting me and I update my mom or vice versa. The latter turned out to be the case, which isn't too surprising.
Now, this isn't a dramatic prediction like s/o hearing from an ex because he was never an ex and we weren't on bad terms . It is still a bit surprising as he's just always been bad with remote communications and we had drifted apart, never really becoming anything beyond friends at one point. So it's quite out of the blue and it's a friendly communication as she said. There is an indirect reference to me in it as well-but this had always been the case.. Like he and my mom and I would go out to dinner and he'd text her instead of texting me to arrange the dinner etc. I know, very rare, very 1800s but that's just how it was.
But there you go, it was the 'first prediction after World' which made Yona think it's immediately after my return lolz. It is because nothing else has happened of importance other than the financial meltdown at work.