First of all, people usually prepare a red envelope when offering tea at a wedding, but the bride may receive two red envelopes. In this case, when the bride changes her name to her parents at the groom's house, the man's parents will each give her a red envelope to show that she is accepted into the family and wish the couple happiness. Secondly, in some places, elders will also prepare two red envelopes, or they may give them to their sons or daughters, which is a blessing for them. In some places, only one can be prepared, for example, one of the parents-in-law can give it, which is also possible.
Therefore, when getting married, the elders should prepare several red envelopes for tea. You can look at local customs to avoid embarrassment when preparing less red envelopes, and people should not care too much about the amount of money, because giving red envelopes is the greatest blessing of elders to newcomers.