What is the ruling on keeping dogs as companions and touching them with one's private parts, and what is required of a man who did not purify himself after touching a dog, then got married and had children?

If a person touches a dog's saliva, urine, or sweat, they must wash the touched areas seven times, one of them with earth or soap. They must also repent if their possession of the dog was unlawful. As for praying with such impurity: if they were unaware of it or believed that the dog is not impure (as per the madhhab of Imam Malik), then they do not need to repeat the prayer. However, if they were aware of its impurity, their prayer is invalid and must be repeated, according to the Shafi'is and those who agree with them. The persistence of impurity on a man's body does not affect his marriage.