No. Jai will not get angree. If it is revealed that Bani is preg in the party and if Jigs try to insult her, Jai will cover up for Bani and say that the baby is his. He is been at the receiving end all these days. He has gratitude for Bani, that to save his "izzat" she has come and living in the house unconditionally and is facing lot of humiliation and is still tolerating everything for his sake and has covered up for him, without asking. Now, he may take Bani's side and say that he is happy that Bani is preg to save her honor. After all he is very soft like butter inside.
Later, he will ask Bani calmly about what the matter is or probably over a period of time, he will discover that Bani is covering up Anu. Anu needs medicine and stuff, which will be given to Bani thinking that she is preg, and Bani will silently pass this on to Anu, which may be witnessed by Jai. He will support Bani all the way, to protect the honor of his family, Anu, and Bani.
Without his knowledge, he will be a perfect husband for Bani!