Would it would be a good idea to ask my brother to set me up with one of his friends?

My friends keep telling me to ask him but I feel weird asking about it and don't want to seem desperate. One of my brothers friends smiles and waves whenever he sees me and glances at me. I can't tell if he is just being friendly or being flirty. Also, when I smile at me he smiles right back. It's not the fake kind. It's the genuine one. How can I tell?