SuweaNSDG, my thoughts are somewhere in the middle of the others.
Here’s what I’m thinking when I read this. You have a doubt. Your conscience is convicting you of something. Listen to that. It doesn’t mean ‘don’t be his sponsor’. It doesn’t mean ignore it and go ahead anyway. It means slow it down.
As his sponsor, and later his God parent, you have an obligation to God and to him. That’s a serious matter. I respect that you are struggling and looking for feedback. It means that you are taking that responsibility seriously. And none of us can stand in judgment for your choices or your conscience.
I do want him to be confirmed, but not at any price. And not at your expense. But, he doesn’t have to be confirmed - pushed through the turnstile on your watch - so that he ‘keeps up with the rest of his class’, ignoring the fact that there’s a reason why you think he’s a candidate, but a candidate with a little more work to do to be ready.
I’d suggest, give him that time to get ready. Pray the rosary for him. Pray several rosaries for him. And let one of those intentions be to ask God to give him a deep, un-ignorable hunger for holiness. A desire to return to the Sacraments. Especially Reconciliation. Pray for the graces from our Lord to fall upon him and have God’s intended effect on him.
I do not think you should follow his mom’s advice. As a reference I would cite Psalm 1:1. Blessed is the man who walks not in the counsel of the wicked, nor stands in the way of sinners, nor sits in the seat of mockers. But his delight is in meditating on the law of the Lord day and night. He is like a tree planted by a stream whose leaf does not wither… I’m sorry if that’s not exact. I’m going from memory here. The advice she is giving you - to mind your own business (nicely put), is wicked. It does not line up with the Word of God.
So you’re left feeling unsettled.
Certainly meet with the priest. And talk directly to him (your nephew). Let him know first, how much you love him. Let him know that you take this role very seriously and want him to live in the abundance of God’s mercy. And that you have a concern when you read his FaceBook. Regardless of whether he is trying to fit in, or whether it is his own desires on that site, it’s there and there’s no denying it or rationalizing it. And it’s a concern.
PuzzleAnnie is correct. You have an obligation to “butt in”. IF he continues to want your support and guidance. And if so, this is the support and guidance you will offer. Explain the goal of confirmation. Explain your role as his Sponsor - to guide him in spiritual matters. And you take that role seriously. Perhaps others would not. You don’t stand in judgment for others’ choices. You can only be accountable for your own stuff.
Tell him you believe in him and think he has what it takes to prepare for this sacrament and to participate in the graces of the church, but some things have to be addressed. And it may not happen on his time line if you don’t - in good conscience - feel that he’s ready. Explain that you are standing with him and he is being presented to God to receive favor, and merit, and graces, and it’s a big deal. He was given graces he did not have before in his Baptism. This Sacrament is quickening those graces inside of him and you want him to be informed and instructed, and properly prepared to receive them so that he knows how to use them.
The ‘choosing’ to continue will ultimately be his choice. You have concerns. You want to address those concerns, regardless of the other advice around you (your sister). IF he wants YOU to be his Sponsor / God Mother, then you have an obligation to do it correctlym and you cannot proceed until you’ve resolved the issues. If he sees the love and deep compassion that drives you to slow the process down a bit while you fine tune a few things, then great. If he doesn’t then you don’t make the choice. You’ve established your healthy boundaries. If you’re going to do this, you’re going to do it right, and present him to God prepared. If he choses someone else who will ‘get on-board’ with the timeline without giving him any grief about his choices or sins, then that is his choice and you respect it. He is free to make that choice. Personally, I think you would be the excellent choice because you love him, and because you want to do it right.
See, you don’t have to make the choice. Yes or no. You have to continue to choose him and pray for him, and follow God’s plan. He has to make a choice. You continue to be attentive to the Holy Spirit and to protect him the best you can by putting up boundaries that will establish a minimum standard. You’re looking for willingness to work with you. You’re looking for the beginnings of a desire for God and His ways. A starting point. You can work with willingness. Willingness is all God asks of us when we’re getting started. So offer God YOUR willlingness to do it His Way, and to fearlessly lead others to God His Way, and to not negotiate your boundaries or move them against your conscience, but to listen to the conscience God has given you for the purpose of protecting you from walking away from His path. Does that help?