Anupamaa is a biased mom but not the way u think.

When that crazy lady Megha tried to attack Aadhya with a knife, Anupamaa was the one who took the bullet for her and almost died. Before that Aadhya had legitimate reasons to hate Maa but shouldn't this selfless act convince her that Maa actually cares. When she came back as Rahi, Maa got arrested because of her yet she was nice to her. When she got arrested because of Doshu, she went out of the way to send him to Amrika ki jail. Maa even tried to reason with Raghav to take complaint back so that Rahi finds peace. The truth is Maa loves only Choti Anu out of all kids because she is just like her- maniacal, dramatic, loud, uneducated, gold digging, cunning, jealous, misbehaved and uncultured. All that supposed neglect was a part of her plan to turn Choti Anu into her permanent horcrux so that even if she dies, someone loves to do her dirty work. She neglected Samar because of Pakhi, Doshu and CA. She got Doshu arrested and now his beloved wife arrested. She physically abused Samar's wife Dumpy. She neglected Ansh for Rahi , Mahi, Pakhi and Ishaani. She and Toshu have spoiled Pari's dietary habits. She glorified her daughter Pakhi's abuser and kidnapper. She hates Mahi because she seems like Kavya clone and has worst of Maya. She tolerated Vanraj abusing Samar's ex GF.

The way Pakhi indulged in narcissistic parenting of Ishaani and the way Anupamaa is indulging in narcissistic parenting of Rahi is same.

Anupamaa doesn't neglect Choti Anu/Aadhya/ Rahi.

SHE ONLY LOVES CHOTI ANU/AADHYA/ RAHI and the reason is her self obsession.

Yeh pooch rahe ho ya bata rahe ho?