In Relation puzzle type, mutual blood relations or other information of more than two persons are mentioned and information about any two is mentioned.
Lakshmi and Meena's are Rohan's wives. Shalini is Meena's step-daughter.
How is Lakshmi related to Shalini ?
Shalini is Meena's step-daughter means Shalini is the daughter of the other wife of Rohan.
So, Shalini is the daughter of Lakshmi or Lakshmi is the mother of Shalini.