Grant Ward's older brother was first referenced during "Agents of S.H.I.E.L.D." season one, when the character revealed to Skye (Chloe Bennett) that his older brother would force Grant to beat up their younger brother, as well as an instance where Maynard dropped their younger brother into a well. Plus, as Zap2It notes, it's possible that Senator Ward is the "senator with deep pockets" mentioned by General Glenn Talbot (Adrian Pasdar) who has a vested interest in bringing Coulson and his team in.
DeKay is best known for his role as Agent Peter Burke in "White Collar," currently set to air its sixth and final season on USA in November. He has also guest starred on a number of other long-running and fan-favorite series including "Chuck," "Scrubs," "Revenge" and more. He will appear in "Agents of S.H.I.E.L.D." on the sixth episode of the second season, "A Fractured Rose."
"Agents of S.H.I.E.L.D." airs Tuesdays on ABC.