I believe seeing as it's your father's cousin, that makes them your second cousin. And their kid to answer your question would be your third cousin
A father and son relationship is called a paternal relationship.
step-granddaughter
If Mr. Sugihara is the father, is son is called his offspring.
Well, it depends how close you are to your husbands family. If you really want to know they are cousins-in-law.
He is your step son.
Your cousin in law
Joseph was the son of Jacob. (Matthew 1:16) He was called the son of Heli (Luke 3:23), this evidently being the name of his father-in-law.
If her son is from a previous relationship, then he would be your step-son.
His name can be changed through a legal name change or through a step parent adoption.
No. You dont have to allow your ex's partner into your home for any reason, especially if they are one that he cheated on you with. If the your son has a good relationship with her, though, maybe you should. Not for her, but for the son. something to think about anyway...
your son and your brother's son will be cousins
your son and your brother's son will be cousins