Los Angeles: Singer Beyoncé Knowles, who severed her professional ties with her father Mathew Knowles in 2011, seems to have ended her feud with him. The "Run the world" hitmaker was joined by her "proud dad" backstage at her 'Formation' world tour concert at NRG Stadium in Houston, Texas, where they happily posed for a photograph together, reports femalefirst.co.uk. Beyoncé's mother Tina, who is now married to actor Richard Lawson, posted the image on Instagram and wrote: "Houston concert proud dad! (sic)" The 34-year-old singer fired Mathew, 64, as her manager in 2011 and their relationship was believed to have been strained ever since. In 2010, Mathew acknowledged that he fathered a son named Nixon with actress Alexsandra Wright after being hit with a paternity suit. He was ordered by a court to pay $12,000 a month in child support. His admission that he had fathered Nixon resulted in his 30-year marriage to Tina ending in 2010, but he remarried, to Gena Charmaine Avery, in June 2013. He recently refused to speculate about the subject of Beyoncé's latest album "Lemonade", after she appeared to reference Mathew's cheating.