What dropper for kids?

I am currently amassing the parts for a new 26 inch build for Progeny number one. He is nine and has the build of a racing sardine so activation weight is key. He currently uses an ancient X Fusion Hilo with an adjustable pressure cartridge however this isn’t ideal as I’ve had to run the pressure so low it’s very slow to return as well as having seen better days generally.

I am aware of the PNW Fern, but that’s direct from the US, which I presume means I would be clobbered for VAT and shipping, putting it right at the top of what I can budget for.

Can anyone suggest light activation or adjustable alternatives?

I fitted a OneUp V2 to my son’s bike, he’s only 9 and built like a bean pole. No issues with reducing the pressure and it still working. Bonus is the low stack height

One up is quite light to activate. I can’t remember an issue with non-activation due to weight. Also a good amount of drop for the amount of post showing.

My lad has a KS E-ten with a bontrager line elite lever and it’s a nice light action. He couldn’t use my reverb. I’ve just got a new bike with a brand X on it with the under bar shifter and the action is really light.

Edit: just realised op was talking about weight on the saddle rather than lever action….

Cheers for the replies. I would have to drill the frame for stealth routing so the Brand X might be a good shout as they do an external option. CRC suggests an activation weight a good 20KG over his though. I’m not normally pro-childhood obesity, but he might need to get some chip butties in him.

I’ve got a light 9yr old on the Brand X 27.2 external routed dropper and it works fine.
It’s shimmed down to 65mm drop using cable ties and works really well.