Family dynamics can be tough to deal with. As we get older we all have more baggage and tend to put it onto others. I can only say, give it to the Father in prayer, then go about your daily routine. He can make a way for the two of you to communicate when the timing is ready. In the meantime, be happy you have a sister. I find praying for my siblings lifts any sorrow or anger i may have. And they always come around. I hope this helps. Blessings.