to me, it's not really about trust. If something happens and the wallet is compromised, you don't know which copy of the key led to the compromise. I'm sure that you have a great relationship with your family members, but I imagine that uncertainty would put a lot of stress on the relationship (you thinking maybe they slipped up somewhere, but in reality it could have been you...)

If you did a 1 of 2 multisig and gave your trusted family member one of the keys, you would always be able to tell which key spends the funds .

I think the benefit of multisig is worth the loss in "get-up-and-vanish" ability.

It's a little more hassle, but some of the miniscript wallets with timelocks might be worth looking in to for your use case. They are usually set up as a 1 of 2 multisig where one of the keys can only spend after a certain threshold of time (so you could give it to a family member as a backup, but you don't have to be quite so worried if they get compromised). But they can have lots of configurations.

The downside to such wallets is that they usually require refreshing your coins every year or so (this means you send every utxo in your wallet to yourself -- it resets the timelock).