What happens to my IBKR portfolio if I pass away?

I have a joint account with wife on IBKR

I have invested fair amount on S&P 500

I funded IBKR through Wise

That money in Wise was not declared in FBR as suggested by my tax guy, he said we will declare only when you withdraw it

So what happens if I pass away?

Can my kids or wife just withdraw it to my bank, without any issue?

People who habe invested in IBKR, must have thought about this at some time?

How would you make sure this hard earned money is transferred to your kids safely?