Buying home with spouse and down payment is inheritance

My husband and I have been married for a few years and we’re about to buy a house together. We have a really big down payment mostly because I got inheritance from my mom passing away about a year and a half ago. Today my aunt brought up that I should make him sign that I get my whole inheritance back if we ever split. He and I have talked about this topic already and we just kind of left it with we are a team and we’re growing things together and it’s not like he was ever after anything I’d end up with because how would you ever even know. He also makes a lot more than me now and I might quit working in a year or so if we have a kid. I don’t want to sour our happy experience suddenly telling him that what we’ve verbally discussed as something that should be obvious and is obvious (that my contributions were huge) has to be in writing now. Anyone been in this spot?