So we dont have to worry about anything bad happening to Arnav and Khushi in Karva Chauth. Aarav is not Arnav's son because if he was than the track would go on much longer with episodes to how Arnav would react and accept his son - to Aarav dealing with the fact that his father is married to someone else other than his mother - to Khushi being able to adapt being a stepmother and how to handle the situation without giving Arnav up.
All of these things would have been necessary if they had planned to make Aarav Arnav's son but they haven't. So please don't worry about this Sheetal track anymore or worrying over the fact that Arnav might break Sheetal fast or if Khushi would give up her life with Arnav for Sheetal and Aarav.
After realizing this I am all set for the Maha episodes and for the day when Arnav finds out how hurt Khushi has been - believe me that day will come soon.