For it is not you who will be speaking, it is the Spirit of your Father speaking through you. (Matthew 10:20)
Your brother may mean well, but he is also driven by subconscious motives he knows little about. By interacting with you, the bigger picture will become a bit clearer for both of you.
A light worker is someone who has let go of her conscious agenda and lets a higher authority decide how to proceed instead. Being a light worker doesn't prevent us from being confused about our own motives, but it does guarantee that every interaction is an opportunity to further our own healing.
Turn away from people with agendas; they are only worth your while if you have one too. The TAO is incredible that way; we are perfectly protected, people with agendas will simply ignore us for we have nothing to offer to them. So if someone with an agenda wants to play with you and you are tempted, know that you still have some homework to do.
The intention matters, everything else is of little importance. Desire to be healed and let the world heal you. Desire to have something else and you will be without compass. Join the WAY and let the SPIRIT speak through you.