I am thinking so much about this crossover ahaha.
Like, I would love Danny to be be a parseltongue and have a pet snake named Basil (after the snake in the champer of secrets). And he would be slytherin but his mom would be the Head of Gryffindor and he would be sad about it and stuff. 
He is still half ghost because some powerful curse went through him and only killed him half or something like that. 
Oh oh, and Sam would be a Gryffindor and it would be a scandal because omg a Slytherin and a Gryffindow are getting along and on top of that they are hanging out with a Ravenclaw boy shdufdf omg pfff
(I know I said Sam should be in Ravenclaw, too, but come on it’s much cooler that way.)
Sam would drag them into all kinds of adventures and Danny would aid her bc he is super loyal but is the one who thinks and stuff bc slytherin. But when SAM asks for something he would do anything sahduidfsdfgfsg
And Danny’s partonus would be a badger and omg STOP ME, OKAY?!

edit: altered the colors…