What field are you in? I'm in social science, and I know of people who've worked as RAs, then gone on to get ESRC 'Future Leaders' grants, which are highly competitive postdocs.
I think the path to a permanent academic post is often a rocky one, taking in part-time / temporary teaching posts, RAs, postdocs if you're lucky. The fact you've had a postdoc already is really good. I don't think RA would be considered a research break, but that's actually probably a good thing if you want to return to postdoc or apply for another postdoc or lectureship in the future. As an aside though, is it normal to have more than one postdoc? I thought funders might not offer them to those who have already completed one, so you might find you need to go from RA to lectureship or a Research Fellow post - which is totally do-able, especially if you're still keeping publications up to an extent.
Of course, things might be slightly different in your field, sounds like you are working in science.
I'm currently finishing my PhD with a nearly two year old in tow, and can totally relate to wanting less stress and more time with the children at the moment!