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What exactly is tradition?
There are many traditions when it comes to marriage. There are so many customs in India, but there is no facility to ask in foreign countries. A similar strange tradition is seen in China where for many years the groom buys accessories for the bride including undergarments. Especially she has the whole family of the child to buy these things. But the husband has to buy the undergarments.
(Read:- When will you get married when you turn 30? You will also be shocked to hear what the girl who keeps asking this question did)
Argument happens in marriage

Rada also takes place in Lagna from this underwear. Marriage breakup due to favoritism, hospitality, dowry or love affair is not new for you. But in China, marriage is broken due to underwear. This is taken seriously here. The marriage was broken because the wife was given small size underwear.
Contrary to tradition

In China, there is a controversy over this strange tradition. Some people are with this practice while some are against it.
understand each other

Marriage is meant to be with each other and to have your man with you in difficult times. So don’t bring such traditions or rituals into your relationship as it will spoil your relationship and only cause you trouble.