The vigil was held Monday night at GoForth Park on Horsepen Creek in Cypress.
The park is named for another deputy who was killed in the line of duty in 2015, Deputy Darren GoForth.
WATCH: Houston Mayor says Deputy Dhalilwal "represents all that is good"
After GoForth's shooting, Deputy Dhaliwal visited his memorial daily, saying at the time, more people need to support officers and do so in a visible way.
"Just wear blue. Wear blue and be proud of that," Dhaliwal said four years ago. "And that shows support to law enforcement. Simple as that."
Now, everyone wore blue for Dhaliwal.
Before Monday night's vigil, people were asked to bring candles, blue lights, and blue glow sticks.
Mayor Sylvester Turner, Police Chief Art Acevedo and former Sheriff Adrian Garcia honored Dhaliwal at the vigil.
Dhaliwal, a 10-year veteran of HCSO, was the first member of the Sikh community to join the sheriff's office. He's survived by his wife and three children.
WATCH: Former sheriff thanks Dhaliwal family at fallen deputy vigil
“Lord, if some dark and dreary night,— Jeff Ehling (@JeffEhlingABC13) September 30, 2019
I must give my life,
Lord with your everlasting love
Protect my children and my wife.”
A note left at the memorial for HCSO Deputy Sandeep Dhaliwal.
He leaves behind a wife and 3 kids.#abc13eyewitness pic.twitter.com/AfzAalDhcM
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