Glenys, this request may get a better response on the Staffordshire board. A moderator may move it for you if they think it would be a good idea.
It certainly looks like there is a connection. Whereabouts in Staffordshire did your Plants and Malkins live, marry and die?
I think you just approach this in the same way that you approach any other families, and trace them carefully step by step. I would check the original parish records if I were you. I'm not sure what is available online for this area in this time, so you may need to order the appropriate films to your local LDS Family History Centre. Of course someone here on Roostchat may have access to these records, so see what other advice you get. I am just wondering if PRs give abode and occupation at this time in Staffordshire.
It may also depend on how many families with the same names are living in the area. If yours is the only one, then it points to there being a connection, however if there were many families by the same names, it may just be coincidence and there may be two Robert and Lydias christening children around the same time. Fairly unusual names I would guess, so you are probably looking at a related family.
What sources have you have checked to get the information you already have?
