Investigators say Ceferino Ramos of Santa Ana was drinking and driving when the collision happened Sunday off Haster Street.
Ramos is now facing at least 10 felony charges according to court records, including DUI, causing great bodily injury and hit and run.
Angela Hernandez Mejia and her partner were on bikes -- pulling their kids in carts just feet from their home.
Three of them were seriously hurt.
Driver arrested after family of 5 injured in OC hit-run crash while out on bike ride
Their 6-year-old daughter and 5-year-old son remain in critical condition. Their 8-month-old daughter is now in stable condition.
The father - Angel Ramirez - is also in critical condition.
On a GoFundMe page, the mom urges everyone to say a prayer for her son, saying he might not make it.