Would it be disrespectful to ask a girl out in front of their brother?

There’s this girl I’ve been wanting to ask out but I know the brother and he thinks I’m a good guy and all so he doesn’t see anything wrong with me. But I typically see her with her brother. I don’t wanna seem disrespectful I don't know if it even is. Like I’m not talking about her looks with him or anything. But what do you think?
Would it be disrespectful to ask a girl out in front of their brother?
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