Araslanova has been detained for two months on a judge's order, according to The Sun.
A murder probe was launched, said the Russian Investigative Committee.
Arselanova reportedly had suffered from depression following the birth of her second child and was put under observation.
She has been detained and her new daughter, her second child, removed from her care as investigators seek to understand her motive.
Bravely speaking about her ordeal, Ivanova said: "We sobbed and couldn't sleep at all.
"The hardest thing is to wake up in the morning and realise this is the reality".
She went on: "I try to hold on for the sake of our children, but it doesn't always work out.
"This feeling will not disappear, I will have to live with this all my life.
"I have been killed with my child, I will never be the same. My children are deprived of a loved one, a little brother.
"Him, each other, and our children, and life in general. We do not hold evil, and forgive everyone, the maternity hospital, the doctors and this deranged woman who was with me in intensive care."
Ivanova and her husband have publicly forgiven the woman who allegedly killed their son.
Arselanova will face a psychological and psychiatric examination before appearing in court.
The distraught mother said "we will not write a statement to the court, because our Volodya is about great and sincere love".
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