Howard (The Christmas Invasion)

Howard was a love interest of Jackie Tyler.

Howard worked at a fruit stall, where he met Jackie. He began delivering to her front door and eventually became involved with her. He began to stay over and left his pyjamas and dressing gown at Jackie's flat.

When the Tenth Doctor became ill after regenerating, Jackie let him wear Howard's pyjamas. When he awoke and put on the dressing gown, the Doctor found an apple in one of the pockets. Jackie explained that Howard sometimes became hungry at night. The Doctor later found a satsuma in a pocket, which he used to defeat the Sycorax leader. (TV: The Christmas Invasion)

When Jackie saw a statue of Rose in the British Museum which was exhibited as the goddess Fortuna, she said that Howard would never believe she'd given birth to a god. (PROSE: The Stone Rose)

Behind the scenes
Due to Jackie no longer living in the same universe as Howard as of TV: Doomsday, ending up in the parallel universe of Pete's World and falling in love with its version of Peter Tyler, the counterpart to her late husband, it is likely that Jackie longer has any relations with Howard, at least of the romantic sort.