If God didn't really have a Son to give....

As I have been contemplating more about what the Father did for me in giving Jesus His true Son to die in my place I have been trying to see things from my sister's point of view (she is a trinitarian) and I just can't reconcile that way of thinking to my God of Love.

If Jesus wasn't really God's son then the Father wouldn't really be able to understand the grief my brother went through when his 3 year old daughter died from a tragic accident.

For if a god who is pretending to be the Father God didn't really have a son to die for my sins and at the incarnation he made another god become his pretend son then when that pretend son died on the cross the pretend father didn't really grieve as a true Father over a true son would.