London Ambulance Service rushed the woman and baby to a central London hospital after they fell off the roof at the back of a property in in Western Road.
Police were called out on Sunday (July 16) at 4.23 pm to reports of a 24-year-old woman and baby falling "from height" at the Southall address.
Ealing Borough police officers are investigating the circumstances of the fall but are currently treating the incident as unexplained.
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