Yes, Pontiac and Chevrolet company share same car body since its under GM (Pontiac, Chevrolet, Cadlillac, Saab and I forgot one more) The cobalt version is the G6/Pursuit which formally was called Chevrolet Cavailver and Pontiac Sunfire (unfortunately they stop that name). They always say, both cars were cousin to eachother.
I would say cousin, Let say.. Your mom is married to your dad's last name, and your mom's s sister is marry to her husband last name... and there you have cousin with different last name but 1/2 or 1/4 same blood. That goes to name "Pontiac and Chevrolet" They are same family under parent of "GM" but with different name get it?