Katrina Kaif, the stunning Bollywood actress, has a sister named Isabelle Kaif, not Isabel. Isabelle Kaif is also a model and has worked in a few films. While Katrina Kaif's personal life and relationships are often in the spotlight, her sister Isabelle's romantic storylines are not well-documented. However, we can explore their bond and any available information on Isabelle's relationships.

As for Katrina Kaif, she has been in several high-profile relationships over the years. Her most notable relationship was with actor Ranbir Kapoor, with whom she had a highly publicized romance from 2009 to 2011. She later dated actor Siddharth Malhotra, and the two were in a relationship from 2014 to 2016.

In conclusion, while there isn't much information available on Isabel (or Isabelle) Kaif's romantic storylines, it's clear that she and her sister Katrina share a beautiful bond. As Isabelle continues to build her career and navigate her personal life, fans will be eager to learn more about her relationships and love life.