Polk County, Florida -- Deputies are investigating two separate hit-and-run crashes in Polk County, just hours apart.
Investigators say it's becoming an alarming crime trend. We've heard it time and time again: a loved one, a little boy, a father, a sister hit by a driver who never stopped to help. Now, investigators hope a new law will make hit-and-run drivers stop.
The most recently deadly crashes both happened in Polk County. The first happened around 2:17 a.m. on Saturday. A cross now marks the spot on Highway 92 near Payne Street in Auburndale where Hector Chavez was killed riding his bicycle.
Investigators believe it wasn't just one car that hit Chavez and kept driving.
"It's astounding to me that one person would hit him and not stop," says Polk County Sheriff Grady Judd. "The thought that two, or three, might have hit him and not stopped is mortifying," says Sheriff Judd.
Four hours later, around 6:40 a.m., investigators received a call from a driver who saw Jill Braddock's body off Clubhouse Road in Lakeland, near Tillery Road. Braddock's sisters talked exclusively with 10 News about the tragedy.
"She would've done anything for anyone," says Kayla Coats, Braddock's sister.
Coats says what makes her little sister's death even harder is that she would have helped anybody. Yet, in the 20-year-old's final moments, the driver who hit Braddock didn't stop to help. Investigators believe she laid there for hours before her body was found.
"I pray that they never lose a loved one, and know what it feels like if someone did that to their family member," says Coats.
SEE ALSO: Pedestrian hit-and-run in Lakeland
Investigators are reviewing two hit-and-run cases in Polk, and those drivers face increased penalties.
The state is cracking down on these hit and run drivers. A new law just went into effect July 1. Now, there's a minimum 4-year prison sentence for anyone who leaves a crash with injuries. Investigators hope it'll make drivers think twice before taking off.
"It would be more expensive to hit-and-run, than it is to hit-and-stay," says Sheriff Judd. "Prior to this legislative action, it was better to take the chances on running and sobering up."
Sheriff Judd insists that the crash isn't always the driver's fault. They could just face a citation, not jail time, if they report the crash.
The Florida Highway Patrol say there were 161 hit-and-run deaths in the state last year. So far in 2014, there are 100 deaths. Too many tragedies leaving investigators looking for drivers.
"The only way I can describe that person is insensitive. The only way I can describe that person is uncaring. The only way I can describe that person is they are now a felon and they need to be brought to justice," says Sheriff Judd.
Meanwhile, grieving families are searching for answers.
"We're willing to forgive you, so you don't have to be afraid to come forward," says Jill Braddock's sister-in-law, Tiffany Braddock.
The Florida Highway Patrol says overall about half of hit and runs are solved.
Tampa Police are still searching for the driver who hit 4-year-old Marterrance Albury in July on Florida Avenue in Tampa.
In St. Petersburg right now, police have an arrest warrant out for Keith Hamm. He's accused in the hit-and-run crash that killed 81-year-old Tomas Melendez in June.
The hit-and-run driver that killed 71-year-old Bill Wren while he was on his motorcycle is still on the loose. The suspect's car is a silver, or gray 4-door 1990s to 2000-year Honda with possible front-end damage.
The Polk County Sheriff's Office says in the US Highway 92 crash that killed Hector Chavez, the vehicle of interest is a 2010-2013 Chevy Camaro, unknown color.
In the Clubhouse Road crash that killed Jill Braddock, the vehicle of interest is a 2007-2009 Nissan Altima, unknown color.
If you know someone who has either of these types of cars that have front-end damage, or if you work at a body shop or know about these types of cars needing repairs, please call Heartland Crime Stoppers at 1-800-226-TIPS
More information on the law and Cohen: