Esha and Ahana are daughters of veteran actors Dharmendra and Hema Malini.
"Neither Dharamji nor Hemaji would want to hurt Prakashji (Sunny and Bobby's mother). The family has decided it's better if Sunny and Bobby stay away," a source said.
"Sorry to disappoint the gossip mongers, but there is no ill-will or bitterness about the Deol brothers' absence from Ahana's wedding," said the source.
"Sunny and Bobby love both Esha and Ahana like they love their own sisters," the source added.
Ahana, who will get married to Delhi-based businessman Vaibhav Vora, had her mehendi function on Friday, and a guest says Esha was "disheartened" due to a shoulder injury.
"Esha was a little disheartened by her shoulder injury at the mehendi ceremony. But her mother, sister, husband and brother-in-law-to-be made sure to keep her spirit alive," said a guest.
Hema said Esha fell on Thursday.
"Esha slipped and fell. She suffered a minor shoulder fracture. She is better now," said Hema.