Among the guests were some people from work. Rachel's sisters Jill and Amy couldn't make it. Rachel's mother Sandra Green was forgotten to be invited, but this led to Sandra having a grudge against Monica during the shower and trying to make her feel guilty. Phoebe eventually convinced Monica to tell Sandra off for being so rude, and so that's what Monica did.
Rachel freaked out because she knew nothing of how to take care of a baby and Sandra suggested she move in, but Ross said Rachel will be a good mother and that Sandra doesn't need to move in.