This isn't actually abnormal to have one person who takes the lead in managing the finances. My sister in law manages my brother and her family's budget and my mom manages the budget for her and my dad. The husbands arent irresponsible and they check with the wife before major purchases. The wife in these marriages is simply the one keeping track, balancing the check book, etc. Neither my brother or father are incapable..it's just how the duties lay out.

And he may just need encouragement that he can be financially responsible, which you are giving him. A lot of people just didnt develop that skill growing up but can build it in adulthood easily with some attention to it. I'm sure you both will manage it. It doesn't sound like hes raring to make super big purchases or anything.
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