De Matteo told authorities that her Honda Odyssey was parked on the street near her home in the Hollywood Hills area one day last month. When she came out the next morning, it was nowhere to be found.
Local authorities have still not found the vehicle, but they are still investigating the matter.
Despite this setback, de Matteo is apparently keeping up her usual routines. On Saturday, she shared several videos of her and her two children out and about at an arcade and at a children's fashion show.
This is not the first time de Matteo has suffered a tough loss of property.
In March 2015, de Matteo's New York City apartment was destroyed in gas explosion fire. Three buildings were burned in the blaze, with de Matteo's home of 22 years being amongst the casualties.
At the time, the star posted a photo of the wreckage on Instagram with a glum caption.
"A hole where my NYC home of the last 22 years once stood... RIP 123 2nd Avenue," she wrote.
Apart from these personal struggles, de Matteo has had a steady stream of work on hit TV shows for the better part of two decades. She played Adriana La Cerva on 56 episodes of The Sopranos and Gina Tribbiani on 46 episodes of the Friends spin-off Joey before landing her beloved SoA role.
On the FX biker drama, she played Wendy, the mother of Jax Teller's (Charlie Hunnam) first-born son, for 35 episodes.
She landed a 20-episode arc on Desperate Housewives before making guest appearances on numerous hits shows, including: Law and Order: Special Victims Unit, CSI: Miami, Agents of S.H.I.E.L.D., Californication and The Mindy Project.
Her latest TV role was Det. Tess Nazario on NBC's Shades of Blue, which just wrapped up a successful three-season run.0comments
De Matteo's next move has not been announced yet, but SoA fans are pining for her to pop up on spinoff series Mayans M.C., which recently premiered on FX.
Photo Credit: FX