I have a male ISFJ coworker who is formally my boss but we get along like peers (he only has slight seniority). We get along by defining jurisdictions. In my own area of expertise, he lets me make all the calls and pretty much outright abdicates any oversight. He just rubber-stamps my decisions. But in his own area of expertise he similarly expects me not to second-guess him unless I can really make a solid case. And when it comes to the kinds of administrative procedures that he's responsible for as my boss, he comes down pretty hard and brooks no opposition. When it comes to administrative procedures and office etiquette, he can come across as patronizing and pedantic. But that's his right as the boss, and I just go along with it. So we get along great.
In their areas of expertise, ISFJs seem to become catalogs or encyclopedias of the conventional way to do things. As far as I'm concerned, that's a pretty strong resume. I don't need people to be on the cutting edge; I just need them to be competent. ISFJs seem to be super-competent in any area they choose as their jurisdiction, so I'm happy to yield any particular jurisdiction to them if they want to claim it.
So that's how I deal with my ISFJ boss. Some things are his jurisdiction and some things are my jurisdiction, and there's a bright shiny line between them. We don't cross the line, and we get along great.
What I said above pertains to work matters. When we're bantering about non-work matters, then there's sometimes a competition. If he has done some reading on a home improvement project, then he'll start dictating procedure to me. But if it turns out that I have some special exposure to the same project and can talk authoritatively about it as well, then he'll listen intently and prepare to yield that subject to me. In fact, I have to watch out not to pretend to have more knowledge than I really have, by playing devil's advocate or just BS'ing. He really will yield leadership to me on a subject if I can prove I have greater knowledge, and I don't want to abuse his trust by pretending to have expertise that I really don't have. (A couple times I've just confused and frustrated him by brainstorming at random without having any particular expertise to back up my suggestions.)
Another ISFJ I know socially is a bit loopier and more freewheeling than my boss (my boss comes across as pretty straight-laced, although he enjoys a good joke too). This second ISFJ and his wife seem to have their jurisdictions pretty well defined; but at the same time he yields a lot of functions to her and she effectively ends up running much of their common life. I think she does it by taking on all the auxiliary functions, which he is happy to give to her so that he's not overloaded between work and home.
For example, one day he was making a trip to the corner store to pick up some groceries; she made up a shopping list and then pinned it into his shirt pocket so he wouldn't forget it. The guy is responsible for multi-million dollar sales of heavy technical equipment, and I joked with him about his wife treating him like a forgetful five-year-old. But he pointed out that he has to juggle a lot of details at work, and he's perfectly happy to come home and be treated like a brainless child and leave the domestic stuff to his wife.
So again, I think the theme is to set up jurisdictions and then observe the lines and let him call the shots in his area. If he's overloaded and sending out distress signals, it might be possible to pry away some of his jurisdictions and make them yours, particularly in some of the auxiliary areas--lighten his load, so to speak.
But I get the impression that it's not wise or practicable to co-pilot together with a (male) ISFJ in a given jurisdiction. Either the jurisdiction is yours or its his, and the other party has to abdicate any claim to substantive input in that jurisdiction (except maybe in occasional individual instances where they can make a real strong case and claim authority by virtue of more knowledge on a subject).
But I have no problem yielding jurisdictions to the couple of ISFJs in my life. When they claim expertise in an area, it's legit. The expertise tends to be based on conventional knowledge rather than cutting-edge knowledge, but like I said above: That's good enough in my opinion. A strong, dependable conventional leader is a true asset. Cutting edge gets dicey sometimes. If an ISFJ can turn in a solid, conventional product reliably and consistently, that's still way above the average.
Oh well, just my impressions about a couple male ISFJs in my life.
By the way, I can't say much about how they raise their kids. In the case of my second ISFJ social acquaintance, it does seem that the male ISFJ takes the lead on establishing rules, morality, and discipline for their children, at least at the head-of-family level. But he and his wife are also a churchgoing couple and tend to both agree to follow traditional roles in that manner.
In the case of my ISFJ boss, it seems like he plays the doting father at home. He takes a lot of delight in exposing the kids to new things and sharing the their fun in little discoveries, and he doesn't seem to play a particularly authoritative role.
So again, maybe it's just about negotiating jurisdictions and then heeding the boundary lines between the jurisdictions. It seems excessively J, but that's how I interact most successfully with these two particular ISFJs. That seems to be the roles we fall into. Maybe that's just me, or maybe that's them and a reflection of being males of that type. Maybe they have to overcompensate a bit and exercise that kind of unquestioned leadership in their chosen jurisdictions in order to be comfortable.
But like I said, I have no problem with yielding jurisdictions to them given their super-competence. And they seem to have no problems yielding jurisdictions to me if I'm demonstrably the better authority in a given area. We mix and match jurisdictions for an equitable balance and then stay out of each other's jurisdictions, and we get along great.