On October 25, Rain shared a video clip of female participants from 'The Unit' giving a huge shoutout to their mentor shouting in unison, "Time to shine! Congratulations teacher Rain!"

The hashtags included, "#theunit #members #congratulatorymessage #soemotional #tearyeyes."

SEE ALSO: Rain pays tribute to late Barbie Hsu during Taiwan concert

On the following day, October 26, the singer uploaded part two of 'The Unit' clip this time featuring all male contestants.  The boys started serenading Rain's "I Do" track clapping their hands when they yelled out with support, "Rain sunbaenim congratulations on the birth of your lovely princess!"

Rain included some hashtags, "#thanks #guys #butigottasayimabitgrossedout", throwing in a witty response.

Meanwhile, KBS 2TV's 'The Unit' is scheduled to premiere on October 28.

Congratulations once again!

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A post shared by RAIN? (@rain_oppa) on Oct 24, 2017 at 11:53pm PDT

#???#parttwo#D-2 #???#???#????????#????#???#???

A post shared by RAIN? (@rain_oppa) on Oct 25, 2017 at 11:46pm PDT