Keep Kai very happy and in a season or more after you get married you will find out your character is pregnant. About 60 days later the child will be born.
You can not have a child with Kai in Harvest Moon DS. But I'm guessing you're talking about Harvest Moon DS Cute, and yes you can have a child after you marry him.
Pineapple.
Kai's Birthday Is Summer 22.The best Gift to give him is a Pineapple.
Go to Ushi No Tane, they'll tell you all you need to know about harvest moon cute :)
He loves Pineapples, so get a basement grow pineapples and present them in summer.
No he won't his AP will stay the same,they won't go up or down.
It is random. There are five different coloring of children and you can have anyone of them if you marry Kai.
To go to the Starry Night Festival with Kai, you must have the affection heart color green, purple or red.
Kai is the only charactor which he LOVES pineapples.
Yes, every Bachelor lives with their wife once the are married.
yes he will
I'm no expert but I've been giving Kai tons of gifts/things he likes and it seems to be working. Try it and see how it works for you! Good luck!