Taarak Mehta Ka Ooltah Chashmah: Sundar wants to tell something BIG to Jethalal

Sundar rang up Jethalal in the show Taarak Mehta Ka Ooltah Chashmah as he wanted to tell a huge secret to Jetha. This was why he did not say a word on the call but asked him to reach park where Sundar would meet Jetha and reveal the details.

What Sundar wants to tell Jethalal?