We are doggysitting my fiancee's parent's 4 year old female coton de tulear. I am a proud owner of a 10 year old female rottweiler. The coton du tulear seems verry traumatized by the presence of my big dog, she doesn't want to eat any food and keeps on hiding in small spaces unreachable by the big dog. Should we keep these animals away from each other for the next week or will the small dog finally adapt to having a new friend around. Maya the rottweiler is very friendly and playful, everytime she gets to close to Abby the coton de tulear, Abby gets very defensive and growls loudly.

Please help me as I don't want to put this small dog through further trauma.

the obvious answer is do not allow them together. even if this was a dog you had adopted, you don't just put dogs together to introduce them - you take days of keeping them seperated & sniffing each other at a baby gate or however but they don't have the opportunity for one to hurt the other.

the little one is probably tramuatized enough just being in unfamiliar territory & not knowing where her people are. since its only a week - I wouldn't take any chances

Suebgone gave you great advice. And whatever you do, don't soothe Abby, it will just reinforce this behavior.