Remote spell charging

Happy Wednesday!
I'd like to craft a spell and give it to my family (who live in a different country) without them knowing it's a spell (because they would absolutely not condone it), under the premise that it is a kind of decorative gift (so as not to have to hide it from them and risk them throwing it away or dismantling it upon discovery). The purpose of it would be to bless them financially and bring good luck in general (keep their income stable, make sure they can cover their bills, have more than enough left for themselves etc.).

My question is: would, for example, a jar spell still work if I am not there to charge it periodically?

If not, how would I go about charging that spell from a distance?

Is a jar spell even the 'best' way to go about it?

Thank you if you took the time to respond, it means a lot!