Are Protestants really our brothers and sisters in Christ?

I heard this on the Catholic Answers radio program. That is that Protestants even evangelicals fundamentalists are our brothers and sisters in Christ despite their antagonism to the truth.
Upon baptism in the name of the father and the son and the Holy Spirit we are all part of the kingdom of God/Heaven on earth, but once we commit mortal sin we are required to receive absolution by those ordained in the manner that Jesus prescribed for this purpose. Protestants don’t do this. How can they be part of the body of Christ our brothers and sisters in Christ even after committing mortal sin and not receiving absolution. Even we Catholics are outside of the kingdom until we receive this absolution?
peace be with you,
Fred

These links should help you understand the Church’s understanding of extra ecclesiam nulla salus. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.
Recommended Reading:
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[LIST]
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Extra ecclesiam nulla salus***
]* Salvation Outside of the Church**
]* What is invincible ignorance?**
]* How can the Church accept salvation for Protestants?**
]* Are conservative Protestants Christians?**
]* Islamics - Hindus- Buddhists - saved without Christian Faith??**
]* Should Catholics try to evangelize Protestants?**
[/LIST]

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