Halloween in London with Halloween obsessed Tween?

[DiscoBiscuits]

We have to be in London over October half-term due to work commitments, much to my Tween's disgust. She is Halloween obsessed, loves picking/carving pumpkins, dressing up and trick or treating around our village. She loves Halloween more than Christmas. It's a huge deal for her.
We'll be staying in the Westminster area so I suspect her usual celebrations won't be possible. What can I book/take her too to persuade her that London is fun and also does Halloween? She is too young at 10yrs for the Natural History Museum After dark party and I'm clueless as to whether there is anything I should be def booking/planning.
Any hidden gems or Must Visits very gratefully recieved

Absolutely take her trick or treating around High Street Kensington on 31st. The residential streets to the north& south of high street Ken are amazing. Lots of Americans living there who go all out for decorating homes and gardens and no doubt have inspired their non American neighbours too.

Some of the houses really are incredible - 3 story high spiders, smoking graves, skeletons, etc.

We used to live close by and my kids & I spent many happy Hallowe'ens in this area.

Be there for sundown.

Tower Hill has a spooky trail for children

Hampton court palace is done up for Halloween. They have sound effects and spooky stories

Harry Potter studios is done up for Halloween

The Royal Observatory Greenwich’s planetarium

Hyde Park has a Halloween discovery day

Phantom Peak

Chelsea Physic Garden

In Chelsea they have a paint a pumpkin event and there's Halloween at Kew

Lauderdale House has a Halloween circus

Sea life and London zoo have events on

Thank you so much, South Ken for Halloween night itself sounds perfect for her.

We are going to the Kew Gardens Halloween trail. It looks great!
Trick or treating in Ken sounds amazing 🤩

High Street Kensington (not South Kensington).

Maybe south ken is good but I've not been trick or treating there 🎃

Thank you - are there any streets in particular we should aim to see or avoid? I am clueless in London but OH new job means we will be there alot now.