Woots, one complete sentence

Lucas came home with a new toy last night but Daddy Sky only noticed it this morning. Check out their conversation below...

Daddy Sky: Wah, how come you have a new Thomas?
Lucas: Ah Gong buy Thomas... (Woots, one complete sentence came out from his mouth)
Daddy Sky: Did you ask Ah Gong to buy for you?
Lucas: ..........
Daddy Sky: You cannot always ask Ah Gong to buy toys for you, ok?
Lucas: OK

Hahah, Mommy Me was impressed with the one sentence as he has been giving me answers in bits and pieces...