So, just to get this straight (no pun intended), you tell your children that to engage in homosexual acts is a sinful thing that will send you off to the depths of hell? So, your children think that their uncle is committing an evil act based on your indoctrination of them. If I was your brother, I'd choose to never speak to you again, making your children homophobic from a young age is bloody despicable. You might benefit from the definition of homophobia.
Faith is a set of teachings.. If you start down the path of faith then you accept its teachings or you don't. I do and my brother doesn't.
My brother has found his path in life that he thinks is right and he is happy, Its his choice and as my faith tells me..I am not one to judge.. He does no care what the Catholic Church thinks. I on the other hand have faith and follow what my faith tells me.. And nowhere does it say that I need to hate my brother.
on the question of Marriage,, Both me and my brother think its between a man and a woman. But to him its just a piece of paper, which he already has as he has a civil partnership from Uk. He does not care about the whole debate. He is open about his life and so is his partner they have good jobs and we all get along.
So you can have faith and have respect at the same time.