Sitting up on his own....

Locks has been sitting on his own for a wee while now... but this morning- I went into his room, and he was 'sitting' in his cot!!! He turned and looked at me like- 'What?" Gobsmacked! how did he get sitting on his own?? The things they do when youre not watching. Maybe its time to put the height of the cot down- he'll be standing next time.