Right.

Anita can drive over in the car she rented, and that way there will be a car in case she has need of such a thing. And then she can wait for the party to start and some people to go in and the correct guards to be on shift.

The house is large and sprawling and open and colorful and lush with hanging plants; there are stars painted on the ceiling and somewhere she can hear water running.

The beautifully papered walls are dotted and streaked here and there with water stains the maid is unable to combat.

No one is paying any attention to Anita.

Cool cool cool. Probably haunted. She can idly mingle for a bit and then see if she can get her bearings and determine which parts of the house are likely to contain an office or other locations where correspondence or records might end up, or determine which other parts of the house have suspicious things in them based on the apparent locations of the guards.

The party is spread throughout the first floor. It's easy to sneak up to the second floor; the designer had, for some reason, failed to put a bathroom on the first floor, and everyone is heading up there.

Well that's very convenient for her go-to lie, then. Anything else seem to be on the second floor?

The second floor has some guest rooms and Lela Donovan's bedroom.

Well, Lela Donovan's bedroom might contain something, even if it's sort of unlikely. Can she slip in undetected and close the door behind her?

Yep.

It is a young child's bedroom.

Hmmm. Eight's old enough for a diary, which could be of some use. She can look under the bed, in a nightstand or sock drawer, in any obvious boxes, and through the closet? Being careful to leave everything as she found it.

She finds a diary.

Lela Donovan LOVES horseback riding. She LOVES her Auntie Portia. She does NOT like school.

Near the end of the diary Lela talks about something scary happening that she doesn't want to write about; the last entry is dated March 1934.

Well, it's not obviously useful, but the kid won't miss it if she dies. Into her purse it goes. If there's nothing else interesting around here then she can head out and work on determining where the adults' secrets are.

Well, there's another flight of stairs.

Well, she can certainly try to climb them. And if anyone stops her, well, there was a line at the other bathroom.

No one stops her!

There is a hallway with two doors.

Woo score. She will be listening very carefully for any guards on this floor, and also listen at the doors before poking around inside them.

There are footsteps from behind the left-hand door.

She'll quietly head into the room that isn't that one, then, and try to keep quiet while she looks around.

She enters a lush, luxurious library, intended for recreation as much as for use. It has extremely comfortable armchairs, like someone threw as much money as possible at having the most comfortable possible place to sit; there's a fireplace that'd be big and roaring if there were a fire in it, with soft animal fur rug in front of it for those cozy winter nights. The walls are adorned with gorgeous paintings of the sea. Near the front is a desk.

She is kind of really annoyed that she isn't her sister. There's probably something in here but she doesn't know how she'd find it in a timely manner, and her purse isn't that big.

Whatever. First she can look through the desk, hurrying up before anyone else comes by to look.

The desk is neatly arranged, with a number of blank notebooks and other office supplies and some photographs. 

One of the photographs is turned down so she can't immediately see what's it of. And she finds an accounting ledger.

What's the upside-down one.

Aha. ...eh, she can take that too, might be useful to have a picture of Probably-Portia.

Can she look through some of the books in a position where she won't be obvious from the door?

Meanwhile--

The house is gorgeous. Cultists sure do love their plants. The openness means it's harder to keep hidden, but the house is crowded enough that nobody is paying much attention to him.

Once most of the guests are there Victoria assigns him to the third floor, which is the best floor for a novice, because Absolutely No One Should Be There. So absolutely nothing interesting is going to happen. But they have to put someone there because it is full of Secrets.