There is no "Big Bed". You have to have 2 separate beds, The husband/wife bed, and you still have your own. You can buy the Husband/wife bed at Chen's shop once you upgraded your home.
Chen's.
You can buy it at the store.
Court her, witness all her heart events, buy a wife's bed, and propose to her
You buy it at chen's store after you have all main characters and have a bed for your husband/wife.
Just go in bed. I think you go in bed together but I am not sure. Eventually the news will come up that you are pregnant and I have heard that it takes up to two years to have the baby.
First get married, then get the biggest house and buy a little bed! After 2 weeks or something like that, you get the pregnancy event, then It takes around 2 seasons and then you have the birth! XXX
You have to pick a bachelor, raise his heart level, meet all marriage requirements (like have all maincharacter villagers, ship so many crops, have husbands bed, etcetc). To have a child, you have to have a kids' bed.
After you get married upgrade your house to the largest size. Then buy the Child's Bed from Chen's Shop (it should be available if you have been married for 30 days). After that keep your spouse happy and just wait to get the pregnancy event.
After you get married upgrade your house to the largest size house and buy the Child's Bed. You or your wife will get pregnant 30 days after you get the Child's bed.
You can't move any of the beds in Harvest Moon...Sorry.
The marriage requirements are the same for all characters. Harvest Moon Island of Happiness marriage requirements: Upgrade your house twice Buy the husband/wife bed See all his/her Heart Events Have a Red Heart with the person Meet all 23 main characters Have Nathan and Alisa currently living on the Island You propose with the Blue Feather. You can buy the Blue Feather from Chen's store once a marriage candidate reaches an Orange Heart Color. But don't propose until their heart turns Red and you've completed all the requirements. Harvest Moon Sunshine Island marriage requirements: Upgrade your house twice Buy the husband/wife bed See all his/her Heart Events Have a Red Heart with him/her Get his/her five-gift Sunstone Raise Mystic Island Meet Nathan, Alisa, and the Harvest Goddess You get the Blue Feather the same way as in Island of Happiness. Just buy it from Chen's shop once you get a marriage candidate to an Orange Heart Color.
You can get a double bed from theharvest sprite station number 2