It is the best thing you can do, if you have full confidence in your brother, it is always better that someone else has your seed phrases in case something happens to you, imagine that all your funds are revalued enough in the future and no one in your family can take advantage of the fruit of your work built in life.
That's it, it is almost the same as sharing your bank details to someone, if you do not have full confidence in the person, we already know that it can happen, I would only leave my seed keys to my mother, not even my wife (if I had it) I would leave my seed phrases, since a relationship can be broken at any time and resentment can lead to many things.
But you can always give your cryptographic data (Seed phrases) to a trusted person in your family in case one day something happened to you, such as your mother, brother or others, because if something happened to you, your cryptos would be lost forever, there have been many cases where millions of dollars in crypto have been lost for things like that.
My mother is not tech savvy and even if I give her access to my wallets, she might not know how to use it. My spouse can access my devices and if she wants she can access my Binance, Kucoin, and Coinbase wallet. However, she will have to ask me for access PIN if she wants to move my assets.
Well, my mother is not savvy when it comes to technology either, but I taught her how to use cryptocurrencies myself, and then I gave her my seed phrase in case something happened to me, it is important that someone you trust must have access to your assets, in your case, your wife is a good option because if something happens to you, your assets could be lost forever.
