Usually by recognition. Like most babies - penguin chicks 'imprint' on their parent from the moment they arrive. Additionally, the parent bird can recognise their chicks calls from some distance away.
Penguins, like most animals, recognize there baby's by smell. Every chick has its own scent. When the mother has the baby, she recognizes that scent and remembers it.
Mostly, this remains a mystery to scientists. Penguin mates as well recognize each other, and that recognition signal is mostly unknown.
By its sounds
sound
penguin has a smooth & slippery face
There's no emote such as a 'Thank You face' emote on club penguin.
in your face
there chick can leave
Man up and ask her out face to face when you two are alone its hard but its worth it :)
Unless Club Penguin releases the blue face paint again, you can't get it. That is an old item.
It's called pepper spray. ;)
lack of food
seal
you face the sensei
dhfsi141 is the code for face paint on cp
Almost as ugly as his face. with that chick car.