Their birthdays were only 11 days apart.
Chantel Osorio, two years older than her sister Tiffany, was turning 24 on March 16 and the sisters were going to New York City to celebrate.
On the morning of her 24th birthday, an account registered to Chantel tweeted: "Great morning to be alive n blessed. Thank you Lord for allowing me another year of you blessings and mercies."
The older sister continued to excitedly tweet about her birthday and the plans she and Tiffany had in the city.
At 5:53 p.m.: "Happy birthday to me !!!!!!!! N happy early st pattys day !!!!!"
At 8:10 p.m.: "My week was rough but my birthday has been goin great. Thank you all that have wished me happy birthday so far !!!"
At 8:11 p.m.: "Tonight is about to be so fun"
And at 9:01 p.m.: "City bound. Hair n makeup"
According to Twitter posts, the girls left New York City around 5 a.m. Saturday.
"Omw (on my way) back to CT now," tweeted an account registered under Tiffany Osorio's name at 5:16 a.m.
Within the next two hours was when state police said the vehicle the girls were traveling in suddenly swerved across the Merritt Parkway, crashed into a tree off the right side of the roadway and burst into flames.
, police said.
"Fire crews extinguished the fire and found two deceased persons inside the car," states a release from Fairfield Assistant Fire Chief Scott Bisson.
State police listed Chantel as the driver and Tiffany as the passenger. The crash happened on Route 15 northbound, about 2 miles north of the ramp for exit 42, police said.
The sisters lived on Deerfield Drive in Stratford. They both graduated from Notre Dame High School in Fairfield.
"Our thoughts are with the #NDFairfield community and the Osorio family as they mourn the loss of alumni Tiffany and Chantel," tweeted the account @SportsFairfield on Sunday afternoon.
Also on Sunday, an apparent former high school classmate of the Osorio sisters with Twitter handle @SassySasha77 tweeted: "I hope what I'm hearing is a rumor two of my friends from high school past away last night."
Hours later, Sash tweeted: "R.I.P Chantel and Tiff Osorio and I know we say things to one another and sometimes you never know when ull never see em again."
On Facebook, Shereffia Francis posted a graphic of the two sisters with the following caption:
"This news was never expected. You were both so young, the good die young and my prayer go out to your family, your parents especially. You ladies will be missed and never forgotten ...watch over us thru tough times."
After high school, Chantel graduated from Southern Connecticut State University in 2009. Tiffany's Twitter account links to the First Baptist Church of Stratford.
A tweet left on Tiffany's account on Saturday afternoon read: "Wasn't very often I chilled with [Tiffany] but I appreciate those days I got a chance to ❤"
Please use the comments section as a space to share your memories about the Stratford sisters.