It happened around 8:30 a.m. on Mamaroneck Avenue near New Street.
First responders found both victims lying in the road and the 6-year-old child was pronounced dead at the scene.
This child's 43-year-old mother was taken to the hospital where she died from her injuries. Witnesses described the mother yelling for the bus to stop.
"The saddest past was just seeing his lunch box, his school bag opened, and all the pencils out and the kid just wanted it have a day at school," said witness Nick Zamora. "And it was his last day."
Police said their initial investigation revealed the school bus was traveling eastbound from New Street and turning left onto Mamaroneck Avenue with the green light.
As the bus was turning, there were several parents and children crossing the street at the crosswalk with the walk sign.
The driver, a 68-year-old man, is cooperating and police say it appears to be a tragic accident. So far no charges are pending.
It's still unclear why the bus driver did not yield to pedestrians, but parents say for years they've been asking for a crossing guard here.
"There's no excuse," added Mamaroneck's Lori Lyons. "No excuse for the village of Mamaroneck to have not have had not somebody out here for years for this to be going on. This should've never happened today!"
Lyons says she used to walk her granddaughter to school every day when she was in Kindergarten.
"I knew in my heart that something tragedy was gonna happen at some point," she added. "It was too many little children and people walking every single morning and traffic was completely not under control. So my heart was very heavy and sad today."
The school was in the middle of end-of-year festivities and will now be staffed with grief counselors.
"Our plan tomorrow morning is to open fully staffed with providers who can support students, and our plan is to band together wraparound services for the family and make sure everyone feels supported, that's what a community does, and that's our intent," said principal Sandra Zadrima.
The bus was en route to Mamaroneck Avenue School at the time of the crash. Several students and an aide were onboard, but no other injuries were reported.
"We are working with authorities to stay abreast of the situation and put any necessary supports in place for our students, staff and families," Superintendent Dr. Charles Sampson wrote a letter to the community. "Our thoughts and hearts are with the entire MAS community."
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