This is a method of evidence gathering that I've included more as a warning. It’s a popular method that you’re going to come across when you work on a product, it just isn't a very good one.
It's also the feedback that many designers fear: "I've just shown this to my husband/wife/mother/son and they think this could be improved by doing x". Where x often involves re-working the whole project but the client values this opinion so much that they insist on it, trumping any rational, carefully gathered evidence that you might present.
It's not just something that comes from design-illiterate clients though. I've been in meetings where well-informed management have suggested changes based on ideas from someone in their family or an old friend. Sometimes they might even be right and at its best it could be an outside opinion that inspires great ideas. However they could be missing a vital bit of context that means it isn’t much help.
Importantly, this is not a method you can repeat reliably. It's a lottery that you can’t bank on: you might get something great but it might lead you nowhere.
Of course we all ask our partner, friends, or housemates for quick feedback from time to time. However in general, the opinions of friends and family shouldn’t be a part of your formal evidence-gathering process. It's the laziest and weakest form of research and there are plenty of other methods for evidence-gathering out there (check out the rest I've written about here).
To be honest family will often give opinions to you whether you want them or not. Alternatively if you do push them into giving an opinion they'll probably just say something positive to shut you up and not hurt your feelings. Neither of these things are very helpful.
If you do come across someone else using these opinions in a meeting (usually when you’re least expecting it) I recommend saying something neutral like "that idea has potential, I'll look into it" or "I'll be sure to incorporate that feedback into the rest of our research". If you can try and gather this kind of feedback early in the design process, during the research phase, and make it clear that late feedback and changes will involve the project taking much longer.
Having explained why you should generally ignore this kind of evidence, there are a few times you can pay more attention to a family/friend opinion that comes your way.
Feedback from friends and family who have actually experienced the product as a normal user or customer should be taken onboard like any other customer complaints or suggestions. If they aren't a customer then their issues possibly aren’t real and nowhere near as valuable a someone who wants your product/service and has been willing to pay for it.
If they're exactly the kind of people you're aiming at with your product then that can be worth incorporating with other customer feedback. Though it's not quite as valuable as a paying customer's thoughts if they match your target audience then it’s useful to know if things appeal to them or not.
If the friend or family member has spotted something that is broken and you can recreate this error then you'd better fix it. It doesn’t matter where you find out about bugs from: their feedback is as good as anyone else's.
Whilst you should always be designing for end users not investors, if they have a fair chunk of money in the company, it can be worth considering what they say to keep them onside. This is especially true if it’s something small: save your battles for the big decisions.
There are no specialist tools you need to use here and the opinions are all (too) free. Ideally get the to demonstrate any problems they think exist, as you might be able to find workarounds for them.
If you’re going to request this feedback anyway try to keep their thoughts very short and focussed on things you can action.