How does the family treat Rikki-tikki after he kills Karait?

The family has always liked Rikki-tikki. When the family first meets Rikki-tikki, he is half-drowned. Teddy even thinks Rikki-tikki is dead; however, the mother and father decide to nurse Rikki-tikki back to health. Even by the first night, Rikki-tikki goes to bed with Teddy. The mother is a little worried about the situation, but the father states that Teddy is safer with the mongoose than without.  

"I don't like that," said Teddy's mother. "He may bite the child."
"He'll do no such thing," said the father. "Teddy's safer with that little beast than if he had a bloodhound to watch him. If a snake came into the nursery now—"

Rikki-tikki proves his value as a protector and snake killer by killing Karait. The family then treats Rikki-tikki even better than before. They let him wander around the dinner table while they are eating. He gets to sit on Teddy's shoulder at the dinner table, and Teddy's mother has taken to petting Rikki-tikki.
That same night, Rikki-tikki once again goes to bed with Teddy. This time, there Teddy's mother does not argue. Rikki-tikki has essentially become a full member of the family.