Police visited the property in Castle Drive, Margate, at about 3.35am on Thursday after concerns were raised for the occupants’ welfare.
Kent Police said two “young children” were taken to hospital by ambulance and later declared dead.
The arrested woman was involved in a road accident at about 2.50am on the A299 Thanet Way and taken to hospital with minor injuries.
She has since been discharged and is in custody at a police station.
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Officers remain at the house in the coastal town, the force said.