A/N: A bonus prequel to pt. 3
When Rose and the Doctor found Pete's world's Donna he was ecstatic. She was exactly like their own Donna, the only difference is that in Pete's world she's extremely smart, and to be honest Rose was a bit jealous of the time Donna and the Doctor spend together. It all disappeared though when he introduced her to Donna as his girlfriend and promptly kissed Rose on the lips. Finding Donna led to finding Martha too. Martha and Rose hit it off and soon all four of them were spending time together.