Sorry if there is an obvious answer but why, if they were together so long and it seemingly took her no time at all to get pregnant via a one night stand, did they not have children? Rob seemed desperate ot be a father to a son, so much he raped his wife?
Or is it just a gaping plot hole best to be left ignored?
Either Jess was onto Rob more thanbwe know and was taking the pill
Or they were just incompatible some couples just can’t make it work and tgen new partner comes along and boom pregnant
Just a theory but i suspect Jess was secretly on the pill
You are probably right there, she did seem to have more freedom than Helen, a job, a house move, the party (fishkettle-gate) so perhaps that was it, hence Robs being keen to jump ship when Helen came along.