My sister says she believes in GOD and still considers herself Catholic but now she sleeps with her BF and has put herself on contraception. Even though she is legally an adult I don’t think she’s mature to do either (she very self absorbed and immature for her age :o ) but she doesn’t listen to a thing I say and if I do advise her or tell her what I think which I have she just ignores me and does what she wants regardless. I know she’s technically old enough to make her own decisions but I’m torn as to what to do about offering my opinion on her actions. What is my obligation to do this? If she’s going to sleep around part of me says maybe being on contraception for her isn’t such a bad thing as she far too irresponsibe to deal with a baby. I’ve told her how I feel several times but I might as well be talking to a deaf person and we always end up fighting about it.
We can’t force adults to make right decisions. Our best and most powerful, effective tools are 1.Love and 2. Prayer. Love encompasses many good acts, like example and truth -telling. If your sister knows beyond a shadow of a doubt that you love her, your words will have much more weight. If she respects you because of your integrity, uprightness, and again, love, she will be more inclined to listen, and to emulate you.
So! By all means tell her the truth. But do it with as much love, compassion and humilty that you can muster. And undergird all of it with rosaries and petitions to your favorite saints. Make little (or big! )sacrifices with the intention to help her.
I say all this because I have similar burdens for people that I love. I will say a prayer for your sister right now as well.
God Bless you, your sister is a blessed girl to have you to care about her and love her.