I am not sure I really had style mojo to begin with. But with that caveat, here is my story.
In terms of getting the body back and losing the weight. It took me 6 months ( all but 2 pounds by 5) with the first baby and no conscious effort ( but I walked a lot; we only had 1 car). With the second it took 9 1/2 months and the third 12 1/2 months. (However I put on less and less with each pregnancy - only about 25 pounds the last time) After all of them I had a brief period when I went under my pre-pregnancy weight.
While my bust and hips are similar, my waist hasn't quite recovered and is 2 to 3 inches bigger than before the first child. While some of that would be stretching, some is back fat that I haven't lost, and don't know if I could.
In terms of clothing I can relate to those who mentioned the motivation of being back in work. With my first, I returned to work (part time) when she was 7 months old and just went back to wearing my old work clothes (I splurged on my first ever wool suit too. My DH brought my daughter into work to see me and she vomited on it!) Also working in the city meant I could still do window shopping on my lunch break, though this changed when I moved jobs.
It is in the area of casual clothing I have had to adjust, and still am. I had so little to wear I bought my first pair of shorts, bought a cotton skirt. As Brianna said, one needs to change your own clothes so much more. Now I have 3 pairs of good jeans, instead of 1 and lots of jumpers (sweaters). Shopping is a lot harder to get time for.
I haven't worked much outside the home since my second child was born and joined YLF forum soon after the third came along last year. It has been helpful in working out how to dress as a MOTG and I feel like I have some good basics (like the jeans, and a denim knee length skirt and 2 new pairs of boots and new glasses). That said I have a way to go, and tend to neglect things like haircuts, accessories and makeup.
I find the commitment of having 3 kids (my daughters are aged 6, 3 1/2 and 19 mo) quite taxing physically and emotionally and there is no way style is anywhere near a top priority (nor should it be). But they are lovely girls and there are beautiful moments. I have been alternating tidying up with writing this post and found a picture my oldest did titled "This is my Mummys Butvfl fas" (beautiful face) How precious is that!