Families and friends have paid tribute to a brother and sister and their friends who were killed in Sunday's A23 horror smash, saying they were the "loveliest people you could know".

Katherine Sharpe, 18, her brother Aaron, 20, and friend Gemma Smoker, 17, were said to have been inseparable.

They were killed with two other friends when the BMW they were in apparently leapt over the central reservation barrier into the path of a Land Rover.

Mitch Treliving, 19, who lived with his mother and brothers at Faygate, is believed to have been at the wheel of the car, which witnesses said seemed to take off as it went out of control.

Also in the car was Danielle Billingham, 17, who had just moved to Crawley and was staying at the Skylane Hotel in Horley.

Friends of the five young people yesterday spoke of their devastation.

Aaron's best friend Liam McDowell described him as a spontaneous man who lived life to the full.

Liam, 19, saw his friend just hours before the 4.30pm crash which killed eight people on the busy dual carriageway just north of Pyecombe.

He said: "He was a very cheeky person, always smiling, the friendliest and best person you could meet.

"He lived life to the full, his motto was 'No fear'. He never had any fear."

Liam, who met Aaron five years ago when they worked at Sainsbury's in Crawley, bumped into his friend the morning of the smash.

He said: "I met him in town. We had a chat and arranged to go out for a drink.

"He was with a friend I hadn't met before."

Liam, from Crawley, found out about Aaron's death the following day.

He said: "I first heard about Katherine and I kept ringing Aaron's mobile. When there was no answer I went round to his house and his family told me what had happened.

"I was absolutely devastated, I couldn't believe it. I still can't.

"I only saw him a few hours before it happened and I was supposed to meet him this Friday for a drink.

"I'm still in shock, it hasn't sunk in yet."

Aaron, who had lived in Eastbourne and Horsham after leaving Thomas Bennett school in Crawley, had only returned to Crawley a few weeks ago.

He was living in Tilgate with friends and travelling to Horsham to work as a window cleaner.

Liam also saw Katherine and her best friend Gemma, both trainee hairdressers, on the day of the crash.

Liam was leaving a club at 4am in Crawley town centre when he stopped to chat with them.

He said: "They were all such lovely people. They will be missed by a lot of people."

Aaron and Katherine's grandmother, Barbara Evenden, also paid tribute to the pair.

She said: "They were lovely, sociable young people and very, very close.

"Katherine would never let Aaron do anything without her, she always looked after him.

"And now they have died together, which in a way is comforting because I could not see either of them being left alone."

Mrs Evenden, who lives with her husband Norman in Copthorne and has four daughters and nine other grandchildren, said the last time she had seen Aaron and Katherine was at a family party earlier this month at the Copthorne Hotel.

She said: "It was Katherine's 18th birthday and they had about 50 friends and lots of family there. Everyone was very happy and I have fond memories of that day.

"Aaron and Katherine were such a lovely pair, they were the sort of people who loved people."

Katherine had been working in her sister's hair salon in Three Bridges and was due to qualify as a junior stylist next month.

Mrs Evenden said she would treasure the last gift sent to her by Katherine.

Her granddaughter sent her a card, addressed to Mrs Evenden using her nickname, saying thank you for her help at the birthday party.

It read: "To Barbie, Thank you for everything, All my love, Katy XX".

Mrs Evenden said her youngest daughter Sylvia Fiddes arrived from her home in Australia yesterday after hearing the news about her nephew and niece.

Vikki Boxall, 19, said she saw her friend Aaron by chance in Crawley town centre the day before he died.

Vikki, who works at The Perfume Shop in County Mall, said: "It was weird because I hadn't seen him for nine months.

"He was his usual cheeky self, such a nice bloke.

"We had a brief chat and then I had to get back to work.

Kirsty Philp, 18, said: "Aaron was a very loving person, very bubbly and caring. Katherine was the loveliest person ever, really sweet, always happy."

It is understood Aaron, Katherine and Gemma will have a joint funeral.

Steve Mohibir, the sole survivor of the crash, is still being treated in hospital in Haywards Heath.

Mr Mohibir, 30, cradled his dying son Marcus, aged two, in his arms amid the carnage.

The toddler lost his fight for life after 24 hours at a specialist children's hospital in Brighton.

Mr Mohibir and his baby son were passengers in the Land Rover driven by his closest friends, Toby and Kate Beasley, from Godalming.

Postman Toby, 33, died at the scene. Kate, 29, died the following day.

Steve's wife Tracey, 30, was at a wedding on the day of the crash and had not joined her husband, son and friends on a day trip to Brighton.