Once our gliders are friendly, they are friendly with everyone, with a small
exception. I think you will have no problems, if you glider gets friendly and trusting of your dad, he should be that way with you.
My wife's glider Gizmo is bonded to her, but also very friendly with me. The one weird exception is this one time Gizmo was sitting on my wife's shoulder, our 13 year old put his finger up to him and he started to jump it like it was live mealworm. (that motion they have when they really want that treat and jump on it.)
every time our 13 yr old put his finger in front of him he would try to grab it with his front hands, if looked like he was going to grab his finger and bite it.
Was very strange, and NONE of the other gliders act that way, I think it was a
fluke thing. one of these days I will have to have him try it again.