The Batkids, all seriousness aside from the reveal, do think this is absolutely hilarious. Like, almost all of THEM have gotten surprise siblings or a sibling returned from the dead and now it's Bruce's turn.
Plus Danny and kids being openly suspicious of this billionaire?? *chefs kiss*
Most of the siblings are eagerly watching but trying SO HARD to not overwhelm Bruce's long lost little brother and his kids. It's bad enough that Damian has got off to such a bad start with the new cousins. They all meet in the hallways now and it's like two semi-feral cats (Dan and Damien) and one mischievous ferret (Ellie) having a stand off.
Dan and Damien: *locked gazes and raised hackles*
Ellie: *trying to decided which BatBurger would be the best option to stage an after school brawl behind*
Dick, in the distance: "I have the sudden premonition that I should check in on Damien today."
Steph, also in the distance: "Something's happening. I don't know what but I want to be there."
Danny, on the phone with Tucker and Sam: "He has a creepy lair in his basement I just KNOW IT."
Batman, lurking: *sweats*
Red Robin, watching Batman Lurk™️: *trying not to laugh*
Duke has only met Danny so far as Signal, but former Teen Hero Danny Fenton spots him and is SO intent on giving this young hero high calorie snacks or even a damn gatorade. If he sees him he will sprint into the closest store if he has to. Duke has a large collection of random post-it notes or wrappers/bottles with affirmations and gratitude Danny wrote. (It goes with other similarly sentimental gifts from Gotham citizens).
Danny hasn't MET Cass personally, but he has taken the kids to a ballet performance once with Jazz when she visited as "cultural enrichment". Surprisingly, Dan liked it more than anyone thought he would. Ballet is incredibly physically demanding, and he can see the beauty in that in their movements.
Jason tho. Jason sees Danny eye sad-wet cat Brucie Wayne with deep suspicion and immediately pushes his way into the Fenton's lives.
Jason LOVES Uncle Danny. Both because it gets Bruce's panties in an absolute twist and because something about the Fenton family just clicks with him. (Danny has absolutely clocked Jason as having returned from the dead. He's not a halfa or a ghost, but he has died and returned from the dead. Probably some type of Revenant? Danny's not sure when or how to broach the topic as they don't know each other well enough yet to our themselves, but Jason being around the family in the meantime will be good for him. Plus the kiddos love'm.)
Bruce is struggling to get his emotional constipation under control long enough to establish a non-hostile or unintentionally-creepy-billionaire relationship again with his baby brother.
Meanwhile Jason is already on the couch playing games with Ellie and Dan. He's already ordered himself a "I'm Someone's Favorite Nephew" mug which he absolutely drinks from at the Manor almost exclusively while he's there. Alfred allows this, given Jason got Danny to agree to meet him.
Jason will happily give Bruce the middle finger but he loves Alfred fiercely. It takes a bit but eventually Danny agrees to meet him. Jason takes Ellie and Dan out for the day to terrorize Gotham, and leaves the two older men to talk.
Danny has a long talk with Alfred, who absolutely has tried so so hard not to cry during all this, but absolutely does eventually. He must have felt so guilty for so long, his beloved friends Thomas and Martha gone, and their youngest son Daniel stolen and he had been unable to do anything but hold Young Master Bruce in both their grief. And yet here he is, a kind father to two beautiful children, telling him he's happy and grew up with a family who, despite a weird, bumpy road, loves him and his kids so so much. Danny doesn't have a photo album available right now, but he and Alfred set a date for Alfred to come back and have dinner to meet both Dan and Ellie, and to look at photo albums together, Fenton and Wayne both.
Alfred reminds Danny of Clockwork just a bit, with his impeccable timing and knowledge/intuition.
Slowly as Danny gets to know Alfred (and Jason, despite how he rags on Bruce, or how Damien seems to have become Dan and Ellie's highschool nemesis, which makes Danny think fondly of fighting-as-bonding in the Infinite Realms) he warms enough to agree, finally, to have dinner at the Manor with the family so Alfred can host, back in his environment as the impeccable Wayne family Butler.
This also means of course that Danny has also agreed to meet and talk with Bruce. (Creepy Billionaire...but also a name that long since lingered in the back of his head and heart though he didn't know why. A photo of a little boy and his big brother that pulls at those same heart strings.)