The friends and family of Peaches Geldof are terrified for her and her half-sister Tiger Lily's future.

According to a source close to the family, they've pleaded with the wayward teen: 'Don't do drugs. Think about Tiger - and don't die like your mum!'

The family is stunned by allegations the 19-year-old daughter of Bob Geldof handed over cash to drug pushers. The claims are said to be supported by video footage seized by the police which allegedly captures Peaches saying to the pushers: 'I'll need valium after this!'

Her mother Paula Yates died of a heroin overdose in 2000, aged 41 - unable to get over the death in late 1997 of her lover, INXS frontman Michael Hutchence, at the age of 37. As a result, Peaches has always sworn she would never touch drugs.

Now her relatives fear the bigger picture. The scandal may badly scar Michael and Paula's daughter Tiger Lily, who adores and looks up to her half-sister.

A close friend who has voiced fears for Tiger, 11, in the past says: 'The whole family is gutted by this. Peaches is headstrong - we all know that. But Tiger loves Peaches dearly and sees her as a glamorous older sister. If the drug allegations are true, what kind of a role model is that?

'Tiger is exceptionally bright and very sweet-natured,' the family friend continues. 'But she's every bit as feisty as Peaches was at that age.

'The obvious fear - which we really hope will be unfounded - is she could go the same way. But what is Tiger to make of a situation where she loses her mother, then becomes frightened of also losing her beloved half-sister, all through drugs? I dare not think what must be going through her mind right now.'

Peaches was allegedly caught on video taken by two London drug dealers - the same ones who filmed singer Amy Winehouse smoking crack in January. Police investigating the pair are said
to have found the clip of her on a PC memory stick.

The camera allegedly picks up the couple talking to Peaches as
she clutches $290 in her hand. The teenager is seen agreeing
to a higher-priced deal, then tells them she will need valium the next day - common practice for drug users to help them 'come down' after a binge.

When police arrested the dealers at their London home, they found a long list of celebrity details and numbers. Sources claim Peaches was included on the list, and she's expected
to be grilled by detectives.

On more than one occasion, Peaches has been likened to her tragic TV presenter mum, inheriting Paula's sexy looks and outrageous fashion sense.

She has followed a similar career path, producing and writing TV documentaries, and even copied Paula's modelling success, with a catwalk debut last year and a deal fronting Australian fashion line Dotti.

Also like her mother, Peaches revels in close friendships with bands, and is dating lanky Faris Badwan, 21, the frontman of UK group The Horrors. Paula began dating Peaches' dad Bob - the mastermind behind Live Aid and lead singer of 1970s Irish group The Boomtown Rats - when she was 17.

The teenager loves being compared to Paula, but has insisted the similarity ends when it comes to the drugs that killed her mum.

Peaches even said on a TV show: 'Teenagers today have nothing to rebel against. They are revelling in taking drugs and drinking and partying and not really changing anything.'

Now her world - and that of her family - has come crashing down because it appears she's on the same self-destructive path.

It isn't the first time Peaches has been linked to drugs, either. In April 2006, she was pictured at a party using a 'bullet', which is a device used to inhale cocaine. But she denied it, declaring:

'That's a picture of someone lighting a roll-up cigarette. 'I've never done coke. My friends do drugs, but I would never use them.'

At the time, Bob Geldof defended his daughter. But in private, he's said to be furious about the effect the newspaper stories could have on Tiger, and gave Peaches a dressing-down.

Bob, 56, later told reporters: 'If she went off the track, I would go f*****g ballistic. She's a pain in the arse sometimes, like all kids, but she's all right.'

She may have got off lightly then, but this time it's different. Family friends say Bob is beside himself with anger and fear, and has banned her from partying for the foreseeable future.

Not only is he worried about Tiger, of whom he's the legal guardian. His other daughters - Fifi, 25, and Pixie, 17 - could also be affected.

'Peaches will have to work overtime to talk herself out of this,' one friend says. 'We don't know if this "secret" tape bears the truth, but one thing is certain - this isn't just a teenager being accused of buying potentially lethal substances.

'This is a teenager who lost her mother to drugs, and she has a little sister who lost her mum the same way. We all hope and pray this is somehow a mistake. Another tragedy for this family is just unthinkable.'

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