All mankind are our brothers and sisters, they may be apostate but God does not stop loving them, He longs for them to come to Him and we are to go and make disciples of all nations and that includes all religions.
Jesus died for sinners, ALL sinners. If you have the grace to believe in Him, then thank God because he has given you that grace.
Our priest tells a story of a huge gathering of religions in India. He was in seminary and wasn’t able to go but watched on TV. People shoulder to shoulder and the leaders of each religion spoke starting with the one with the most adherents. After each finished their talks the crowd went wild clapping, yelling and they’d get the crowd calmed down for the next one.
The Catholic went last and told about Jesus, His divinity, His humanity, His love and when he finished there was no cheering, no clapping, no unbridled exuberance, the seminarians watching on TV couldn’t understand it...until the cameras finally went to the crowds, they were on their knees, crying, praying.
The aftermath was that thousands were baptized a year later.
At which point they become our brothers and sisters.
We preach the message. If it is accepted, we baptize. If it is rejected, we shake the dust off of our sandals and move on. Not my words, by the way. Stating that the Lord God and Allah are both the god of Abraham is wrong. There is no equivalency, and trying to make the equivalency puts another, false, god before or equal to the Lord God.
I was in Africa some years ago and had dinner with missionaries from Kenya who talked about having 5,000 people come to Sunday services in 3 sessions at their small church- some families walking overnight from their villages to get there
In Mozambique I met Methodist men who walked 3 days through rebel infested bush (savage mindless murderous rebels) to get to a Methodist church conference
They were protestants but I believe Catholicism will make great strides in Africa and the 3rd world even as the West secularizes or falls into the gray water religions of the churches of “Our Lord of Wass Happening Now”