Dads can sometimes be difficult to read, but it's fair to say that if yours is shadow-boxing in the air, he's either really, really mad or really, really happy.

Aaron Donald's dad is the latter. When he NFL son brought a brand-new Dodge truck into his driveway and said it was his, Mr. Donald expressed his emotions in the best way he knew how: fist-fighting the air.

His son, who just won the Rookie of the Year award with the St. Louis Rams, managed to capture the celebration.

Just bought my dad a new truck hahah great feeling

A video posted by Aaron Donald (@aarondonald99) on

Donald is still working on a rookie contract, which pays a handsome wage as the No. 13 pick from from the 2014 NFL Draft. But if he stays the course, Donald could turn into one of the league's better defensive lineman and earn himself a much, much bigger payday when his free-agent contract comes up.

Just imagine the kind of truck he'll buy his dad then. Forget the truck: Imagine the violence his father will commit in the name of celebration.

In seriousness, though, it's a great gift and tribute to a man who undoubtedly helped his son achieve his football dreams.

Signed my contract today just the beginning #Rams

A photo posted by Aaron Donald (@aarondonald99) on

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