He is the grandson of Hall-of-Famer Bryan Hextall, the son of former NHL player Bryan Hextall Jr. and nephew of former NHL player Dennis Hextall.
Hextall's son, center Brett Hextall was drafted by the Phoenix Coyotes in the sixth round (159th overall) of the 2008 NHL Entry Draft. With that selection, the Hextalls have a chance to become the first family to have four generations play in the NHL
And since its relevant to the topic, I'm pretty sure the Patricks were the first father-son combo to play in the NHL, on account of Lester's 46 minutes as a Ranger goalie. If there is somebody earlier, it would be interesting hearing about it.