Meghan Markle and Kate Middleton make a case for sisters-in-law outings

As much as tennis fans were drawn to see whether Serena Williams will reclaim her Wimbledon title, as the first mother to reach the finals of the tournament since 1980, there were a couple of other women worth watching too. Saturday marked the first time Catherine, Duchess of Cambridge, and Meghan, Duchess of Sussex, got to have a day out without their husbands. So far, they’re making us wish for a sister-in-law of our own.

Kate Middleton has been blessed in the sister department already. We’ve long witnessed her close relationship with Pippa. Meghan Markle, on the other hand, has a half-sister we know best for her controversial interviews with the press. Even the closest sisterly relationships can be fraught with old or new rivalries and grievances, of course. Nonetheless, it’s often an intense, if unbreakable relationship.

A sister-in-law, however, is a different matter. Sisters-in-law can be rivals too — in personal accomplishments, in suitability for the family, in affection from their spouses’ parents, in popping out grandkids, in hosting gatherings, and on and on. Or they can be allies and eventually friends. Right away, they share the fact that they were drawn to this other family, and the fact that they are the outsiders coming into it. They can bond when the family does its crazy thing (oh, the value of a shared eye roll!) and help each other through challenges.

This Saturday outing is a sign that Kate and Meghan seem to be more friends than rivals. We don’t know the official reason William and Harry opted to sit this one out, but it provided their wives with the perfect chance to shine. Kate grew up attending the tournament, and now she’s a patron of the All England Club. Meghan has been attending matches for a few years thanks to her friendship with Williams, which dates back to 2010. Even if they didn’t already have tons to talk about, this shared fandom makes things easy for them.

Then there is their fashion. If their relationship were less harmonious, we could imagine Meghan either mimicking the more experienced Duchess of Cambridge’s proper dresses, or upstaging them with something flashier. Instead, each was in her own lane. Kate went with what she knows works for her, sporting a Jenny Packham white dress with black polka dots. Meghan went in an entirely different direction, with a twist on the button-down shirt and pants outfits she’s worn to sporting events in the past. This Ralph Lauren combo was more eye-catching and less business casual, thanks to bolder blue stripes and crisp white wide-leg pants. In contrast with Kate’s neat, loose hair, Meghan brought back her signature “messy” bun, because why not? These aren’t rivals in the least. They are friends with some shared commonalities — like the fact that they apparently don’t sweat — and completely separate identities.

So, maybe this is overanalyzing their style. You can’t argue with the camera, though. From the moment they stepped out of the car, they were talking and laughing with each other. What are their shared jokes? Are they scheming to invite fellow royal box attendee Shonda Rhimes to join them for a drink later? Are they marveling at Serena? Debating the song of the summer? We can’t know for sure. Good sisters have to keep their secrets too.

Read more from Yahoo Lifestyle:

• Kate Middleton and Meghan Markle plan girls’ trip to cheer on Serena Williams at Wimbledon

• Prince Louis’s christening: See what Kate, Meghan, and Pippa wore

• Pippa Middleton rocks ruffled maternity dress as Kate and Meghan plan Wimbledon trip

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