ABC7 News observed the balcony at the scene of incident. The fourth floor appeared to be roughly 40 feet from the ground level.
RELATED: 4-year-old boy falls from 4th story balcony in Sunnyvale
A family friend and neighbor told ABC7 News the 4-year-old is in critical condition and celebrated his 4th birthday last week.
The child landed on Moulik Soni's first floor balcony.
"We just heard a sound and looked out and there was a kid on the balcony," Soni said. "We weren't sure which apartment or whom he belonged. He was bleeding, but he was breathing, so I called 911 when I saw that."
A 4-year-old boy fell from the fourth story balcony at this apartment complex in Sunnyvale. A family friend tells me the child is in critical condition and just celebrated his 4th birthday last week @abc7newsbayarea pic.twitter.com/8HwgPoJLX6— Jobina Fortson (@JobinaFortson) March 26, 2019
According to the family friend, the boy's mother was home at the time of the incident. She apparently went to do something in a bedroom for just a few moments, as her son made his way outside.
Investigators called the fall an accident. CPS and the district attorney were contacted per protocol.
"We were kind of nervous and didn't really know how to react, but we knew the first thing to do was call 911," Soni said.
The family friend told ABC7 News the boy suffered head trauma and was in surgery until well after 11 p.m. on Monday night. The boy's Sunnyvale community is hoping he'll be OK.