Harry Dunn's mother has said she has no hope in US President Donald Trump helping them to get justice over their son's death.
Anne Sacoolas, the 42-year-old motorist allegedly responsible for the crash, claimed diplomatic immunity and was allowed to return to the US.
Harry's parents, Charlotte Charles and Tim Dunn, said that they had heard nothing from US officials since their White House meeting with President Trump.
"President Trump said he was trying to sort something out in October. I don't believe him or have any hope in him at all," Ms Charles told Piers Morgan and Susana Reid on Good Morning Britain on Wednesday.
Her comments come after Ms Charles revealed yesterday that she had requested a meeting with both President Trump and Prime Minister Boris Johnson.
During the interview, Mr Dunn also criticised Foreign Secretary Dominic Raab, telling the GMB hosts that the Tory minister has never given them his contact details.
"We feel like we're being fobbed off. They're giving these mundane answers to fob us off," Mr Dunn said.
"I have never had his contact details. I've seen him once in a meeting and once on Monday but no details were ever given to me," Mr Dunn added.
In an emotional plea made to authorities involved in bring Ms Sacoolas to justice, Ms Charles said: 'I don't think we are dealing with the reality of him not being here.
"Keeping our fight going is like keeping him alive but we have to keep fighting because if we don't no one else will.
"The fire in our bellies will not go away. We cannot allow people to come over here and allow people to take precious lives away.
'We've been completely wrecked since she took Harry from our lives. The longer it takes the more determined we become."
Last night, the Prime Minister and Mr Trump joined other Nato leaders at a reception hosted by the Queen at Buckingham Palace in London on Tuesday night .
Outside the palace, Harry's mother Charlotte Charles spoke to reporters about her hopes of discussing her son's case with Mr Johnson and Mr Trump.
Standing in front of a large banner featuring a photo of her son and the message "Justice 4 Harry", she explained the family had sent an email to the prime minister's office requesting a meeting with the two leaders.
She added: "We had an email back to say that our email was having some attention and consideration, it's probably just a standard email, but us as a family would not be able to give up the opportunity of being in London just in case they ever did ring and say we've got a few minutes.
"We don't think it's going to happen but we couldn't sit at home just in case."
Harry's family brought their case to Mr Trump at a visit to the White House in October, with Mrs Charles describing the president as "gracious" and "welcoming".
She added: "But it was quite evident within a couple of minutes of being in the Oval Office that he wanted us there to try and smooth things over as such and have us meet with Anne Sacoolas who was in the next room.
"He was probably hoping that we would just then go away and grieve."
Mrs Charles said it was "upsetting" that the UK and the Queen were hosting Mr Trump while he was "harbouring" the suspect in Harry's case.
On Wednesday the family launched legal action against the Foreign Office.
They claim the Foreign Office had “no legal power to make such an agreement” over the immunity granted to Anne Sacoolas.