a baby or an alien

Hello, I am translating a parragraph and i found the text difficult to translate. it's the description of a baby but i don't find the way to translate it without making it sound as if it were an alien. :confused:

Can anybody help me???

SOURCE:
Ben was Fanshawe's son and he had been born just three and a half month ago. "I pretended to admaire the baby, who was waving his arms and drooling whitish spittle down his chin, (...)"

my translation: "Simulé admirar al bebé, quien agitaba los brazos y babeaba una saliva blanquecina que cubría su mentón ..."

Please help me! Any correction is welcome.

CLarabe

The kid is an alien. I saw him once at the supermarket. Does the writer mention the ET's pointed ears and the little antenna on his head that keeps going up and down and has a tiny blinking light? If not, he will.

haha! poor baby

then, it's not just my personal impressio... i think the author was not very fond of kids.

i 'll my best to translate it as acurate as possible.

see you!!

clarabe..

I think your translation is just fine.

thank you! ;)