It has been impossible ignore the rise of ‘My Family’ stickers in Australia: cutesy, chalk-like stick portraits of mum, dad, and the kids, perhaps a dog or two, slapped to the rear of at first conspicuously ‘family’ cars (Taragos, Odysseys, etc.) but now all manner of vehicles. Part of the appeal of these stickers (available from local newsagencies) is meant to be their sheer diversity and capacity for personalization: as one purchases each stick-person separately, all manner of combinations are possible. Not only can one select a dad playing golf, barbecuing or wielding a power drill, but any combination of family members: two, one or no mums; ten kids or zero.
However, with queasy inevitability, the family portraits one sees are almost invariably nuclear, and the stickers have been adopted as a self-satisfied badge of heternormative, middle-class nuclear pride. In these stickers we see unselfconsciously displayed the driver’s immense satisfaction at having hit the jackpot of cultural ‘normality’—wife, husband, two or three or more kids, dog, cat, white picket fence. One does not see single-mother or father families, nor families without children. The stickers are the almost exclusive domain of those who must announce that not only have they observed to the letter the scripts of the dominant ideology, but observed a kind of retrograde fantasy of it (a romanticization of domesticity reminiscent of the post-war years).
The dubious idealism of these stickers is double-layered. Not only do the arrangement of family members tend to reflect traditional constructions of family that a large number of us ‘fail’ to achieve, but the cutesy stick-images themselves recall the family portraits crayoned by young children: a willfully ‘childlike’ vision of domestic life. What we are seeing is surely the glamorization of a middle-class, pre-feminist domesticity through an ‘innocent’ point-of-view. We are left with an image that begs us to imagine, to celebrate: ‘family, remember how it used to be?’
The stickers have been subject to a recent backlash, however, expressed most pointedly in parody stickers that announce “f*@! your family” or, less pointedly, announce as the driver’s ‘family’ a cheekily lone individual. It’s easy to understand the irritation leveled at the original stickers’ outdated expectations, at the triumphant normality of those who display them, and at their repressive restamping of desirability and ‘normality’ itself.
It's all done with mirrors 
I’m rather a fan of the backlash sticker subtitled “Making my family”… I’ll leave it up to your imagination as to what the stick figures pictured were up to.
I think the bigger problem is that they spout the ideals of being able to portray diversity, but there’s not much at all; like you say, the push is to promote the nuclear families, but there’s the inherent problem that the people who put these stickers on their car unironically are likely to all have the same mindset as the others: the very small cosmetic difference between the stickers belies that they’re mainly displayed by the singular demographic to which they’re aimed.
And I fucking hate them.