From a biological perspective, monkeys and pigs belong to completely different species, and there is no concept of "mother-in-law relationship" in their social structure.
In real life, monkeys and pigs are wild or domestic animals, and they do not form complex relationships similar to those in human families, including mother-in-law relationships.
From a logical and biological perspective, there is no mother-in-law relationship between monkeys and pigs, let alone discussing whether they are compatible or not.