Every two weeks, Alena Konecna packs her bags to leave her own mother and daughter at home in Slovakia and travel some 400 kilometres (250 miles) across the border into Austria to take care of someone else's mother. As citizens across the continent prepare to vote in May's European Parliament elections, 40-year-old Konecna is an example of those who regularly take advantage of one of the EU's most important pillars: the free movement of labour.