Very Horny Brother

My younger brother (20) is a root rat according to my older brother (25), adding he would fuck anything with a pulse. I'd been away at university and returned home to the news my younger brother was getting married. Sudden I thought and after a talk with my older brother I (23) found out the reason. He had gotten his girlfriend pregnant (18), nothing unusual about that I thought. But then my brother added, he also got her mother (36) widow pregnant. Had also been fucking other women and as of now none of them are pregnant. The wedding our father's way of keeping a lid on the scandal, threatening to stop his allowance got him to agree. The wedding is this Saturday, and my brother is on a very short leash as they say. His future wife and mother-in-law already living on the family estate. My brother isn't going to go to university as he dropped out of school and trained as a mechanic, another of our father's conditions on him. Our mother is quite happy about becoming a grandmother, not so on how. Strict limits on my brother's access to his trust fund has also been put in place. His actions aren't a matter you mention in front of our parents either, so the less said is better. He was such a timid boy growing up and had really changed over the last 6 years. But I hadn't noticed it before and was somewhat shocked on hearing of his actions on my return.