Eryk Pelka: 'I want them to suffer the same pain as Daniel'
2 August 2013 Last updated at 22:53 BST
The mother of Daniel Pelka, Magdelena Luczak, and and her partner, Mariusz Krezolek, have been jailed for life for the four-year-old's murder.
Daniel Pelka's biological father, Eryk Pelka, has reacted with anger at the abuse of his son - but Daniel's grandmother has blamed the British authorities for not intervening earlier to stop her daughter from killing him.
Steven Evans spoke to Eryk in Poland.