Mumbai: Actor Akshay Kumar's son Aarav has received his first degree black belt in Kudo, Okinawa and Goju Ryu Karate Do. The action star says he has received the "best gift ever". Akshay took to his Twitter handle and Instagram account on Sunday to post an image of his son wearing a blue uniform with a black belt. The “Airlift” actor tweeted: “It's a son day all the way! Honestly, I can't express my happiness, I've received the best gift ever today”. “My son started training when he was just four years old. And today, after nine years of hard work he got his first degree black belt in Kudo, Okinawa and Goju Ryu Karate Do! "Some joys cannot be expressed in words, this one tops the list. But I'm feeling so proud, had to share it with you all...Overwhelmed, can't stop smiling, proudfather,” the 48-year-old wrote.