The 'incident' occurs just before Christmas so this is all super new to everyone and NOBODY is happy to be there tbh (except for Helena) 

Non clones in attendance - Felix, Delphine (team potions megaforce are going to fix this mess damn it), Cal (BRIEFLY - nearly splinched himself trying to aparate away from Mrs. S)

Backyard Quidditch match! Manning household rules (AKA NO RULES) - Rachel and Sarah spent a good part of the match intentionally slamming bludgers at eachothers faces - both end up with matching broken noses. Match ends when Helena literally jumps off her broom IN MID AIR to catch the snitch (anything to win for Sarah). It would have been about 20000x worse if she hadn't landed in a snowdrift. 

Sarah overhears Mrs. S talking about Rachel (aka the fact shes actually a Tom Riddle style orphan with nowhere to go on the holidays which is why she invited her) and then decides to use this as ammo in an argument with Rachel (who had just said something particularly nasty about Felix in Sarah's defence). Super hectic duel ensues in the family room - Jennifer walks in and nearly gets a hex right to the face so runs to get Mrs. S, who gets there in time watch Sarah almost but not quite dodge Rachel's sectumsempra spell which catches her behind the ear. WOW SHE IS MAD

Rachel and Sarah get their wands confiscated for the remainder of the holiday, and SUCH A LECTURE ABOUT DARK MAGIC (Sarah also rolled out some shady spells). They're then promptly banished to the back yard to get rid of garden gnomes in fumey silence. Sarah kinda sort of apologises for saying that and promises not to tell anyone else and lets on that she's an orphan as well and Mrs. S is her foster mum. Rachels silence seems a bit less fumey after this. 

Beth spends the first day trailing helplessly after an incredibly upset and angry Alison whose struggling with how furious her family are about this and how her almost girlfriend is not only muggleborn but also an identical (HOGOD when her family finds out about this too). She gives up when Alison calls viciously her a mudblood and spends a sulky afternoon bouncing spells off the wall of the house and blocking them as they rebound. Right up until she misses one and ends up stupefying a visiting neighbour. 

Alison - upset about getting the cold shoulder from Beth (although lets be real she totally deserves it, don't call people mudblood Ali god damn) Ali gets into the firewhisky which leads to a tearful, alcohol fueled heart to heart with Mrs. S about how she's effed it all up with Beth and such. Beth walks in on the exchange and Mrs. S gently coaches them back to speaking terms with eachother. Then promptly changes their sleeping arrangements so their no longer sharing a room. Alison then rats on Cosima and Delphine (SHES A SLYTHERIN WHAT DID YOU EXPECT?). 

Cosima and Delphine are pretty reclusive for most of the holiday (an aside they were given Felix's bed to sleep in). You know working on the 'crazy potions' wink wink. Well right up until Alison ratted on them. They are both SUPER unimpressed especially since if they want to hang out together they now have to do it in the KITCHEN (aka in direct view of Mrs. S). This does result in a little bit more research actually happening though. 

Mrs. S would not have invited everyone if she realised how much bloody chaperoning/preventing people from accidentally killing each-other would be involved tbh

Helena, when not stalking Sarah ends up spending the balance of her time helping Mrs. S and Jennifer cook and bake in the kitchen. It's... messy, and Helena is VERY stubbourn which is why dishes served at christmas dinner included a huge jello shaped like a turkey, sardine pie with mustard and deep fried anchovies.