You are going to screw your kids up royally if you don’t stop attacking their faith and trying to impose yours.
They were baptized into the Lutheran Church. They live with their mother who is raising them Lutheran. Support their mother as best as you can, and stop countering her parenting and her faith formation of your children.
And then, pray for them. Answer questions when they are older. Take them to Mass with you, never pressure them. Be available when they are older and able to understand. Have Catholic books in your home available to them. They cannot understand now, but one day may be open to Catholicism if you haven’t alienated them and their mother (and your own parents). They will become confused if you keep this up. Lead by example, be gracious and kind. Support them in their Lutheran milestone moments.
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