Six-month-old Millie Wyn Ginniver, from Blaenau Ffestiniog in Gwynedd, was a passenger in the car that killed Anna Williams, 22, from Penrhyndeudraeth, who is thought to be her aunt.
Their Ford Fiesta collided with a lorry on the A487 in Gwynedd on Thursday.
The driver is named locally as Millie’s mother and Ms Williams’ sister Sioned.
Sgt Emlyn Hughes of North Wales Police has appealed for witnesses to the Gellilydan crash.
The road was closed for about six hours after the crash while police investigated the cause.
The next of kin of all three have been informed and are being supported by police.
“Every time we’ve stayed there, there seems to be accidents,” she said.
“One week there were three accidents. There is a whole series of bends on the road, the worst of the bends is the one near the house.
“What originally prompted us was there was a danger to us and to guests and visitors.
“There’s a parking area just beyond the gate. It’s a dangerous bend and a blind corner. It’s very dangerous to pull out onto the road. Anything pulling out of the layby can be rear-ended.
“We wanted to put up a notice saying ‘danger concealed entrance’ but we weren’t allowed to do that. It is something to do with standard signs that are allowed.”
She said “slow” warnings were painted on the road but added: “I really thought they would take the point that with this high number of minor accidents, it was only a matter of time before a major accident occurred.
“Now tragically that major accident has occurred.”
A Welsh Government spokesman said: “The trunk road network is regularly inspected and any safety-related defects are addressed as a priority.
“The government is absolutely committed to improving road safety and reducing the number of people killed and seriously injured on Welsh roads.”