If I have a seed in addition to a 2-of-3 vault, it would be like a 2-of-4 in a sense, wouldn't it? That is: with a seed, it's as if you had the original wallet.
But it's also another complication since I need to find where to hide this seed. And I think it's already quite difficult to manage the 3 different locations with the 2-of-3 multisig.
If you do not understand the concept of a multi-signature wallet, it is better to read about it before you make any decision to create it. In short, in the case of Khaled, you need any two signatures to perform the transaction. Imagine it as a door, and that door opens with any two of the four keys, meaning that you only need two keys. To open the door, but you cannot do that with one, and if two keys are lost, you can still open that door.
For more please read:
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Set Up Multi Signature Wallet -
Help me to create a multisignature wallet with Electrum -
https://en.bitcoin.it/wiki/Multi-signature