Regulus Arcturus Black
Sirius, the brightest star in the night sky, has an apparent magnitude of about -1.46. Its absolute magnitude is approximately +1.4. This extreme brightness is due to its proximity to Earth, as it is located about 8.6 light-years away. Sirius is actually a binary star system, consisting of Sirius A and Sirius B.
If your brother-in-law is the brother of your spouse, he is not related to your brother. If your brother-in-law is the husband of your sister, then he is also your brother's brother-in-law
brother
He is brother your brother in law.
The simple subject of the sentence in the question is brother.
No, your brother's brother-in-law is not related to you unless you and your brother both married children of the same parents and they had another brother. but the the brother-in-law relationship is not through your brother and his marriage, but because he is the brother of your spouse. Technically, the proper introduction would be, "This is my brother's brother-in-law" as there is no direct relationship between the two of you.
Your brother and you is correct.
Your husband's brother is your brother-in-law.
His sister.
Your wife's brother is your brother-in-law.
Your brother-in-law is either the husband of your sister or the brother of your husband. Your brother-in-law is not your husband's brother-in-law.
Your wife's brother-in-law is either your brother or the husband of her sister. In the first case, her brother-in-law's brother is you or one of your other brothers. In the second case, her brother-in-law's brother is not related to you.