Why should Preesha be guilty bcoz she is not the mom of Saransh?
Preesha even though she didnt give birth to Saransh, she gave him a heartbeat, she took a lot of pain and suffered a lot of taunts of being a unwed mother and characterless woman for raising Saransh and did all motherly duties for him
Just like Sharda Maa didnt give birth to Rajeev and Rudraksh but did her motherly duties towards them same way Preesha has done.
Actually Mahima should be really guilty as she didnt even remember her son and even though she gave Saransh birth, she didnt do anything as a mother for him for 7 years and made Preesha suffer so much pain.
Even GPS and Vasu should not forget how much pains Preesha took to raise Saransh and they should not tell Preesha to give back Saransh as he is a not a toy
Saransh even if he finds out that Mahima is his real mom even then he shud remember Preesha giving him heartbeat and raising him as a child remembers the touch of a mother.