Sports gambling is advertised on television at times when children and young people are watching. There are calls for the government to control this. Dr Heather Wardle, a gambling behaviour expert from the London School of Hygiene and Tropical Medicine, said, "It’s hard to prove what harm is being done because it’s a generational thing and the harm comes much further down the line. We’re creating the conditions that normalise gambling for a generation". The gambling industry has announced voluntary curbs on television advertising. Stephen van Rooyen of Sky UK, maintains the TV ad ban is meaningless unless the industry also curbs advertising on other media. Rooyen stated, "The gambling industry are ignoring the fact they spend five times more on online marketing than they do on TV. By cutting TV ads, they’ll simply spend more online, bombarding people’s smartphones, tablets and social media feeds with even more gambling ads. A proportionate and responsible limit to gambling advertising across all media is the right thing to do". The voluntary reduction also does not prevent shirt sponsorship, ads that run around hoardings in stadiums, so that gambling firms will still feature prominently during live sport.