(CNN) -- Maria de Villota's family have expressed their thanks for the public support they have received after the Marussia driver lost her right eye following a Formula One crash.
The Spaniard, one of only two female drivers contracted to an F1 team, sustained serious head and face injuries when her car collided with a stationary truck during a test event on Tuesday.
De Villota underwent surgery at a British hospital following the incident, but it was too late to save the 32-year-old's eye.
"We, the family, are supporting each other here at Maria's side and we take great comfort from the remarkable medical care she has been receiving," her sister Isabel said in a statement released by the Russian-owned team.
"We remain positive and this is due, in no small part, to the overwhelming expression of love and support for Maria from every corner of the world.
"We would also wish to thank everyone at the Marussia F1 Team for all the care and attention they have shown us over the past few days."
Tuesday was the first time De Villota had been behind the wheel of Marussia's MR01 car, although she did conduct a test for the Renault team last year.
"Maria remains in a critical but stable condition," added De Villota's sister.
"While there is no further news than that at present, we have at least been able to take encouragement from the fact that Maria has remained stable throughout since the accident, particularly during the first night following such a lengthy surgical procedure as she experienced."
The De Villota family has a rich motorsport heritage. Maria's father Emilio was a Formula One driver between 1976 and 1982.
The only other female driver currently involved in the elite division of motorsport is Susie Wolff, who is a development driver with Williams.