These are the biggest sibling rivalries in the clothing business

Sibling rivalries are the clothing business' latest trend.

Increasingly, some of the most popular apparel stores are finding themselves outpaced by the very brands they created.

This week, Racked reported that J.Crew would be bringing its successful sister brand Madewell to some of its stores. Madewell is known for its denim but prides itself on its effortless and timeless clothing that doesn't chase after fast-fashion trends. While J.Crew has struggled in recent years, Madewell has become one of the company's sweet spots.

J.Crew isn't alone. H&M, American Eagle, Abercrombie, and Gap have all increasingly found themselves being outshined by their sister labels, which are helping to boost sales at the parent company overall.

Take a look at some of these stores and their wildly popular sister brands:

J.Crew and Madewell

citing poor quality and expensive prices

8% in 2016 10% decrease 12%

Madewell has been around since 1937. It was

It was acquired by J.Crew in 2006 under the direction of former CEO Mickey Drexler. Drexler set his mind to make it huge and put S

"We are cleaning and simplifying, so we're steering the collection towards the classic, straightforward, and effortlessly sexy design and taking the things Madewell has done best — tomboy pieces, denim, and leather — and giving them a bigger platform," told WhoWhatWear in 2013.

The secret to Madewell's success has been knowing its customer and not jumping on fast-fashion trends. Its focus is on good-quality, longer-lasting clothing, which historically had a lower price point than at J.Crew.

Drexler said that increasing prices contributed to J.Crew's downfall.

Gap and Old Navy

Former J.Crew CEO Mickey Drexler, who oversaw the takeover of Madewell, was also responsible for creating another popular sister brand during his time as CEO at Gap Inc.

In 1993, Drexler set up Old Navy as a more budget-conscious store to appeal to low-income shoppers.

saving grace.struggled in recent years,

"Maybe there is a little bit of difference [in quality], but not enough that is making me feel like I need to spend more money," Dana McKay, a 39-year-old mother of two who does all her shopping at Old Navy and has done so since her college days, told Business Insider in May 2017.

Old Navy is better at jumping on trends than its sister brand Gap.

"I wouldn't call it fast fashion but they are replenishing the merchandise more frequently. You are constantly getting new stuff into the store and it tends to be what the consumer is craving," Bridget Weishaar, an analyst at Morningstar, told Business Insider.

Old Navy also has an efficient system in place whereby it can trial products in smaller batches in order to see how successful they are before rolling them out on a larger scale, a spokesperson for the brand told Business Insider. This helps the brand to gauge what sells well.

Gap Inc. did not immediately respond to Business Insider's request for comment.

American Eagle and Aerie

American Eagle's sister brand Aerie has taken the underwear market by storm, winning over the hearts of millennial shoppers with its body-positive ad campaigns.

In the fiscal year of 2016, American Eagle's same-store sales grew by a modest 1%, while Aerie was up 23% in the same period.

This growth gap defined 2017 as well. Same-store sales at Aerie were up 25%, 26%, and 19% in the first, second, and third quarters of the year. Meanwhile, at American Eagle, same-store sales grew by 1%, 0%, and 1% in the same period.

Aerie's decision to nix airbrushed ads has paid off and helped sales to skyrocket in the past four years. It's been an effective way to appeal to customers who favor authenticity over anything else.

Meanwhile, American Eagle has fallen out of favor as there is greater competition among teen and low-cost fashion retailers such as H&M and Forever 21.

American Eagle did not immediately respond to Business Insider's request for comment.

H&M and Cos

The H&M group has several brands on its roster, but its second-largest by store count (as H&M does not break out the individual sales numbers of its sister stores) is Cos, which markets itself as offering higher-priced and better-quality clothing.

In its six-month report for the period from December 2016 to May 2017, H&M

In 2017, group sales slowed with a growth rate of 3%, which was below the company's expectations, and this was largely attributed to weakness at H&M itself.

Abercrombie and Hollister

America's sweetheart, teen retailer Abercrombie, has fallen out of favor in recent years and been accused of losing relevance with its customers. It's been desperately trying to win them back by revamping its image, promising fewer logos and ditching its overly sexualized ad campaigns, which were not resonating well with shoppers.

But the impact of this hasn't yet been felt in its earnings, as same-store sales at the brand declined steeply throughout fiscal years 2016 and 2017.

Its lower-priced and beachy, California-themed sister brand, Hollister, has become the company's unsung hero. Since the third quarter of the fiscal year 2016, its same-store sales have grown from flat to positive. Year-to-date in fiscal 2017, same-store sales at Hollister are up 6%, while at Abercrombie, they're down 6%.

Hollister's strategy to woo back teen shoppers by remodeling stores and hiring top designers seems to be working.

Abercrombie did not immediately respond to Business Insider's request for comment.

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